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Gravity and the dead weight of the tower push down and the ground pushes back up and small air movements push from the side. The size of the foundation depends on the strength of the supporting ground. A foundation placed with maximum of efficiency.

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This activity is part of our Engineering in the Classroom tool for educators! Click to learn more about the Next Generation Science Standards (NGSS) for engineering, make connections to NASA and discover more standards-aligned activities.
› Explore the tool

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Educator Guide: Spaghetti Anyone? Building with Pasta | NASA/JPL Edu

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Students use the engineering design process to build a structure to handle the greatest load and gain first-hand experience with compression and tension forces.

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This website explains how it is more important to focus on the base before you start thinking about making it the tallest.

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How can twenty sticks of spaghetti, a yard of tape, a yard of string, and one marshmallow help build a stronger team?

The Marshmallow Challenge has become a popular exercise in which small groups are asked to build the "tallest free-standing structure" out of the materials provided. The teams have eighteen minutes to complete this task including the entire marshmallow on top. It's a fun and instructive exercise that allows teams to experience simple lessons in collaboration, innovation and creativity.

The challenge has been conducted with business school graduates, CEOs, architects, engineers, and even kindergarteners. There have been surprising findings for which groups perform most successfully. Surprisingly, recent business school graduates are among the worst performers and kindergarteners often excel at this challenge. The children don't spend time fighting to be the leader of the group. Instead, they just start playing and in the process begin prototyping. Business school grads spend most of the time talking, planning and building, which means they don't have much time to change the design when it finally comes time to put the marshmallow on top which is usually too heavy for the structure that was built.

The teambuilding lessons from this challenge include:

Always test assumptions through prototyping: Participants think that marshmallows are light and will be easily supported, but when teams start building the structure, it suddenly tips it over. Only through realizing that every idea has value and then prototyping various solutions can the teams find out what works.

Don't focus on being the tallest. When the instruction is given that the tallest will win, teams assume that height will win the contest. As a result, they wrongly focus on how high they can build the structure instead of the stability its base. Many times, companies try to grow too fast before they have a solid business.

Use what is available. Development of every product has limitations and teams can only use what they have and not get resources they want to build something better. In business, there is never unlimited resources or the perfect environment to grow.

Use only what is needed. There are some things that are given in the exercise that do not need to be used like the string. Teams have to figure out what is useful and what needs to be discarded in developing any solutions.

Give up perfection. Teams start out dreaming about building an elegant structure like the Eiffel Tower. They have to give up this idea of perfection and build something (even if it is ugly) that works that can be "good enough" to win.

If you're looking for a fun way to kick start a meeting or get a team into a creative frame of mind, try running a marshmallow challenge of your own. Is your team up to it?

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How can twenty sticks of spaghetti, a yard of tape, a yard of string, and one marshmallow help build a stronger team? The Marshmallow Challenge has become a popular exercise in which small groups are asked to build the "tallest free-standing structure" out of the materials provided.

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P5 Group 7: Wide bases and Isosceles triangles 

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P5 Group 7: Wide bases and Isosceles triangles 

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The pairing of a wide base and an isosceles triangles is an easy way to make stable, free standing structure, as shown below.

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This website explains how the forces of gravity interact with structures, and how the engineer can create a building that can support its own weight. This most definitely applies to the creation of towers.

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by Chris Woodford. Last updated: July 23, 2017.

Amazing buildings make amazing cities. But what makes amazing buildings so.... amazing? Apart from being lovely to look at and wonderful to work in, an amazing building is quite often the product of very clever engineering. In other words, it's built not just on rocks or earth but on cutting-edge science and technology. Amazing buildings can withstand earthquakes and plane crashes. They can heat themselves using little more than the Sun's gaze. They use advanced materials in very advanced ways so you never have to paint the woodwork or clean the windows. Let's take a closer look at some of the science hiding inside the places where we live, work, sleep, and breathe!

Photo: Steel skeleton: You might look at a building and think the walls hold it up, but a modern building is just as likely to be supported by a hidden steel framework. In this partly constructed community center, a web of giant, interlocked, steel girders acts like a skeleton, resting on concrete foundations. Bricks are being built around the outside of the steel frame to give an attractive, traditional appearance, but they're largely cosmetic: the majority of the forces holding the building up are going to be supported by the steel inside.

How gravity works against buildings

All kids like building things! Whether we're stacking LEGO® blocks or playing cards in the living room, sticks in the forest, or sandcastles on the beach, we're all architects and builders at heart. Think back to the last time you made something in this way. What was the biggest problem you faced? One of the things that would have worried you was the possibility of your building toppling over once it reached a certain height. That's also true in the real world, where the number one problem any builder faces is keeping their structure upright.

The trouble is all to do with gravity: the magnetic-like force of attraction between any two objects in our universe. On Earth, we see gravity as a tendency for things to fall toward the floor, but gravity always work two ways. If you drop a pen, it does indeed fall toward the floor-but the floor also jumps up by a microscopic amount to meet it on the way! The force pulling your pen down toward Earth is exactly the same size as the force that pulls Earth up toward your pen.

Now gravity usually pulls things straight downward, but it can act in other ways too. Suppose you built a really tall brick wall. We can think of gravity acting on it in two different ways. We can see it as a collection of separate bricks, with gravity pulling on each one separately. Or we can think of it as a solid wall with gravity pulling on the whole thing, just as though all its mass were packed into a single point in its center. The place where an object's mass seems to be concentrated is called its center of gravity. For a simple brick wall, the center of gravity is slap bang in the middle of the central brick.

So what makes a wall fall over? If the center of gravity is over to one side (if we've not built the wall straight or if we've built it on sloping ground), the force of gravity acting down will produce a turning effect called a moment. If the moment is small, the mortar between the bricks can resist it and keep the wall upright. But if the moment is too large, the mortar will break apart, the bricks will topple, and the wall will collapse.

Artwork: Why walls stay up and why they collapse. Left: If a wall is built upright or on flat ground, the center of gravity (blue dot) is directly above the center point of the wall's foundations (yellow dot), so the wall is stable. Right: But if a wall is built on sloping ground, the center of gravity is no longer above the center of the base. Now gravity (red arrow) creates a moment (green arrow) that tips the wall over. The higher the wall, the greater the mass above the center of gravity, the greater the turning force and the more chance the wall will collapse.

Now this doesn't just apply to single walls: it applies to entire buildings. If a skyscraper is 200 m (650 ft) tall and a gale blows it hard at the top, there's a huge turning force trying to tip the whole building over to the side. That's why tall buildings need deep foundations (where a significant part of the building is constructed underground to support the part that's above ground). If something tries to push the top the building to one side, the foundations effectively resist and push it back in the opposite direction! In other words, they help to counter the moment that would make a building topple to one side.

How a building supports its own weight

It's not only sideways, toppling forces that buildings have to withstand. If you've ever picked up a brick or a piece of stone masonry, you'll know it's reasonably heavy. Now imagine how much all the bricks or blocks of stone in a skyscraper weigh. Add to that the weight of the floors and ceilings. And then, on top of that, the weight of all the office equipment, furniture, and people in the building. What you have is a gigantic lump of weight pushing straight downwards... which immediately raises two questions.

First off, why doesn't the whole building sink straight into the ground? Of course, if you build your skyscraper on quicksand or in the middle of a swamp, it might do exactly that! But most people build on reasonably firm earth (soil) or rock. There will be a certain amount of squeezing downward if you build onto earth, but once the soil is fully compressed (squeezed) it will be almost as solid as rock and further compression shouldn't be an issue. It is possible, however, if floods or drought make the earth too wet or dry, that the ground beneath the building could shift or sink. This problem is called subsidence and has to be tackled by pumping tons of concrete under a building to shore it up.

The other question is why the building does not collapse down on itself. You can probably see that the bottom stories of a building are going to be under much more pressure (the force acting per unit of area) than the top stories, because they have to support more weight. So if you built the lower stories of a building from cardboard and the upper ones from brick, you'd run into problems quite quickly. But you might be able to build the lower stories from brick and the upper ones from cardboard. And you could even build the lower ones from cardboard if you used some extra supports (such as steel pillars) to help support the weight of the bricks in the stories up above.

Photo: Question: How do you build deep foundations for a tall building without digging away tons of earth? Answer: Use a foundation drill like this. These amazing drills can sink foundations over 30m (100ft) into the ground. Some can drill holes about 2.5m (8.2ft) in diameter! Find out more in our main article about drilling technology.

How buildings balance forces

Buildings in the real world are not like towers made of LEGO® or sandcastles. Those structures are usually made of solid material, whereas a real-world building is mostly empty space. Not only that, but the "empty space" inside a building usually has to support the weight of people, office equipment, or factory machines. Having solved their first problem (how to make a structure that doesn't topple over), architects and builders immediately turn their attention to another problem: how to make a hollow building that can support its own weight and that of its contents and occupants. This comes down to understanding where the forces are in a building and how they are transmitted from one part to another-or, in other words, how gravity is channeled through the various parts of the structure.

Artwork: There's more than one way to balance the weight of a building. Instead of chaneling it through heavy vertical walls and horizontal floors, Richard Buckminster Fuller's famous geodesic domes distribute force evenly through an outer "skin" of interconnected triangles. This creates an uninterrupted interior space much more cheaply and using much less material. As he pointed out in his 1954 dome patent, you need 23kg (50lb) of wall and roofing material to shelter 900 sq cm (one square foot) of floor space, but you can achieve the same end with only 0.35kg (0.78 lb) of geodesic dome. That works out at abut 600 times less building material! Furthermore, Fuller claimed his domes were strong enough to withstand winds of 240 km/h (150mph). Artwork courtesy of US Patent and Trademark Office from US Patent 2,682,235: Building Construction by Richard Buckminster Fuller, published June 29, 1954.

To make a building that is both strong and hollow, we need to put horizontal and vertical structures together to do different jobs. For example, the outside walls usually play a vital part in keeping the building up, while the inside walls help to separate one room from another and the floors (which are often ceilings too) give us something to stand on. But it's not quite that simple when you start to think about forces. Imagine you're sitting on a sofa in the middle of the floor on the top story of a large house. If there's no wall directly underneath the floor where you're sitting, what stops the sofa crashing through the floor? The total gravitational force acting downward (the weight of your body, the weight of the sofa, and the weight of the floor) is transmitted sideways through the structural members of the floor (which may be anything from simple wooden bars called joists to heavy metal ones known as girders) to the walls at the side. The force then channels down through the walls to the floor. The force of the walls pushing down on the floor is exactly balanced by an equal force when the floor pushes up on the wall. If that weren't the case, and the two forces weren't exactly balanced, either the walls or the floor would be moving. The fact that buildings and structures don't move tells us that the forces acting on them must indeed be balanced-and that's why we call these sorts of constructions static structures.

If you've ever seen a building being demolished by a crane with a wrecker ball (a ball and chain), you will have noticed that buildings can stay up even with most of their walls knocked away. That's because some walls in a building are more important than others and not all of them support the building's weight. The main, structural walls are called load-bearing walls and they're usually built from solid brick or stone. Knock one of these out and a large chunk of your building will probably collapse. The other walls in your building may simply be cosmetic ones built from a lighter material such as plasterboard. You can easily remove these walls without affecting the building's ability to stay upright and keep its shape (which is known as its structural integrity).

When skyscrapers were first built, they had elaborate wooden frameworks inside them to support their weight-lots of internal walls to support all the force pushing down from above. Gradually, though, as people found they needed (and often preferred) wide open spaces inside buildings for offices and factories, architects found ways of getting rid of the internal walls. Having slender pillars or columns was one obvious way to do this. Another option was to have extremely strong outer walls and sturdy horizontal girders running through the floors and ceilings to carry the weight of the building across to this "outer skin". A third option was to have a strong central core, sturdy floors running out from it like the petals on a flower, and only a relatively light outer skin made from steel or glass.

Tension and compression forces in buildings

Artwork: Left: The vertical wooden beam is in compression: it's being squeezed by the weight pushing downward and by the ground pushing back up. Right: An identical wooden beam, laid horizontally on top of two vertical beams, is in compression at the top and tension at the bottom, while the vertical beams that support it are both in compression.

The parts of a building can behave in different ways when large forces act on them. Suppose, for example, you're back on the sofa in the middle of the floor on the top story of your house. Suppose I reach in through a window with a crane and place a 50-tonne weight onto the floor right next to you. It's quite likely the floor will immediately collapse and you'll fall through the hole I've just made. But what makes the floor collapse? Obviously, the beams supporting the floor cannot withstand the weight we're subjecting them to-but how exactly do they break? And why does the floor collapse rather than the walls? The answer is all to do with tension and compression.

Suppose you have a wooden beam standing vertically. You can support lots of weight on top of it because there's something solid underneath transmitting the force of gravity directly to the ground. The more weight you put on the beam, the more you squeeze it. If you could measure the beam accurately, you'd see that it shrinks just a tiny bit with every extra bit of weight you pile onto it. When a beam is loaded like this, we say it's in compression: it's being subject to compressive or squeezing forces.

Now suppose you balance the same beam horizontally between two similar, vertical beams-much like balancing the floor of a house between the walls. If you pile weights onto the beam, it won't behave quite the same way as it did before. The entire beam will start to bend, but the top and the bottom will bend differently. The top of the beam will be squeezed (by compression forces) and it'll get slightly shorter, while the bottom will be stretched and it will become a bit longer. We say the bottom is in tension (it's stretching) and we call the forces that do this tensile forces.

Photo: Making reinforced concrete. These construction workers from the US Navy are spreading wet concrete from a truck onto a grid of steel reinforcing bars. When the concrete sets, the steel bars will give it added strength. Picture by Lt. Edward Miller, courtesy of U.S. Navy.

We can keep piling load onto the beam for just as long as its internal structure can cope with these forces. At some point, the wood in the beam will splinter when the individual wood fibers can no longer cope with the tensile forces at the bottom. Then the beam will snap in two in the center, at the bottom, and the floor will collapse.

Like wood, concrete is good at withstanding compressive forces, but not so good at coping with tensile forces. Ordinary concrete is a superb material for making vertical walls, but it's much less effective for making horizontal floors because it's quite brittle: it will snap at a weak point just like wood if you pile too much weight onto it. You can make concrete much stronger by pouring it into a mold that contains a grid of rigid steel bars (often known as "rebar"). Concrete strengthened in this way is called reinforced concrete because the steel gives the concrete extra strength and helps it to withstand tensile as well as compressive forces. Next time you see people constructing a huge concrete building, bridge, or other structure, take a look and see if you can see the steel reinforcement bars or rebar grid before the concrete is poured in.

Make way, heavy load!

Tension and compression aren't the only forces that buildings have to cope with. From the tallest skyscraper to the simplest bridge, every static structure also has to cope with varying loads. An office block will weigh far more when it's full of people, computers, desks, and photocopiers than it does when it's empty, and the people who build it have to take that into account. Similarly, bridges have to cope with varying forces both from things that drive over them and the weather, which can lead to bending and twisting ( torsion) that might make them collapse. Every static structure has to be able to cope with a mixture of dead loads (its own basic weight) and live loads (the weight it carries when it's occupied or being used), so working out what those are and how big they will be is an important part of building design. You can read more about this in our detailed article on bridges.

Cardboard constructions

Photo: Top: Placed upright, a cardboard toilet roll can support three heavy books. Bottom: Placed flat, it can't even support one!

If you have a hollow cardboard tube (such as a kitchen towel holder or empty toilet roll), you probably know that it's rather better at withstanding some forces than others. Try it! If you place the tube vertically, you can stand quite a lot of weight on the end. You could, for example, put quite a lot of heavy books on top of the tube without it showing the least signs of stress. The weight of the books will try to squeeze the tube downward. In other words, the tube is in compression. Placed upright, cardboard tubes are structurally very sound because there are solid walls going all the way down from the top to the bottom to support any weight on top. Also, because the walls have a circular cross-section (you get a circle if you slice through them), the forces are spread through the structure: no part of any wall is loaded more than any other. Cardboard tubes are so strong that one Japanese architect, Shigeru Ban, has made a feature of them in lightweight temporary buildings, such as emergency housing for refugees.

But suppose you try to make the floors of a building out of cardboard tubes. You can probably see we're heading for trouble here straight away! If you place a cardboard tube horizontally and try to stand things on it, you'll soon squash it flat. That's because there's only hollow, empty space between the place where you're applying the force and the ground. The curved, cardboard walls are simply too thin to channel the forces around them so the whole structure collapses. In other words, cardboard tubes are not very good at withstanding compressive forces when they're placed horizontally.

What this tells us is that some materials work well in buildings when we use them in a particular way and they work badly if we use them in other ways. In other words, it's important to understand the properties of materials if you want your buildings to work effectively.

Choosing the best materials for a building

Steel, concrete, and wood are three of our most versatile building materials-but there are lots of others, including composite materials and plastics. Architects and engineers use many different materials in their constructions and choose one material instead of another for a variety of reasons. Concrete is the material of choice for large structures such as bridges and tunnels, because it's strong, long-lasting, waterproof, fireproof, relatively inexpensive, and easy to mold into curved as well as straight shapes.

Suppose you were designing a skyscraper. How would you go about choosing the materials? First you'd need to know how many stories high the building has to be. That's worked out by calculating how expensive the building land is, how much the building will cost to construct (an unknown, but you can guess roughly), and how much profit the owners want to make. Let's say you think the building will have to be 100 stories high. You can now estimate how much it will weigh and how much weight it will have to support on each floor. So you can start to design some sort of a structure that will support that much weight for that height into the air. Probably you'll use steel and concrete for the structural parts of the building (where the weight will be supported), but you won't want to build a solid concrete block! So you might hide the structural parts in the center of the building and make the outer parts entirely of glass. But glass is heavy, so you'll need to factor its weight into your structural calculations too. And you'll need to figure out how the weight of the glass is going to be supported by the floor or ceiling of the story it attaches to, or by the outer steel skin of the building.

You'll also have to think about keeping the building's occupants warm and comfortable. If you're making the facade from glass, it's going to absorb huge amounts of solar heat (something known as passive solar). That's great in winter, because it will help to reduce heating costs, but in the summer it could make the building unbearably hot. So maybe you'll want to use some sort of tinted or reflective glass that cuts down the solar gain a little? To figure all this out, you'll need to understand something about the science of heat energy and how it travels around inside buildings.

Photo: Passive solar gain: the large glass windows in this spacious wooden building help to absorb heat energy from the Sun. Picture by Donald Aitken courtesy of US Department of Energy/National Renewable Energy Laboratory (DOE/NREL).

With the basic structure of the building decided, you'll turn your attention to the interior details. You might decide to make all the internal walls from steel panels that can be moved around as necessary to create flexible office space. Or maybe you want to use wooden floors or paneling to create a warmer and more friendly feel? Hopefully, you'll opt to use properly sourced sustainable wood supplies. For that, you'll need to understand why cutting down trees has an environmental impact on places like topical rainforests and how that can be minimized.

You can see that every aspect of a building's design needs meticulous consideration. Making a building is not just a matter of coming up with something that looks good. It's about creating a structure that can survive all the strains of the modern world. For that, you need to be just as much of a scientist as an engineer!

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How buildings work: the science of forces and static structures

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by Chris Woodford. Last updated: July 23, 2017. Amazing buildings make amazing cities. But what makes amazing buildings so.... amazing? Apart from being lovely to look at and wonderful to work in, an amazing building is quite often the product of very clever engineering.

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An anonymous pinterest user gives a few good examples of towers. Each of them is a good example of center of balance, as the marshmallow is supported by building-like supports in each example.

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Trial and error allows you to find the best solution. Though it takes some patience, this method gives you multiple tries to find the right solution.

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Triangle is the most stable shape because it distributes any pressure applied evenly.

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Garret gives great information on bridge types. This is useful for towers, too!

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What is a bridge? A bridge could be anything as simple as a log laying across a creek. Or as sophisticated as the Golden Gate Bridge. A bridge is just something that helps us cross an obstacle, whether that be a river, ocean, swamp, canyon, or highway. At the most basic level, there are three types of bridges:

But it gets a little more complex than that. We also have truss bridges.

Somewhere the Cantilever fits in.

In addition, sometimes Cable Stayed bridges have their own category, while other times they are simply a sub-class of Suspension.

Six Bridge Types

For ease of use, Garrett's Bridges classifies six categories of bridges.

Each of these is unique enough to be analysed separately. Each have their place in building model bridges, but we focus most on Truss Bridges.

Beam

The most simple and common type of bridge used in the real world. This type can be quite effective, even if it isn't very beautiful. Most highway bridges fall under this category, made from I Beams and reinforced concrete.

While we're on the subject of beams, it is worth noting the different types of beams. Beams can be made into different shapes, and used on any bridge type. The most simple is a solid square beam. Engineers figured out that a solid beam is not the most efficient, so they started using different shapes. the I shape beam is quite common, as well as the L and T beams. You might also see a hollow square shape used now and then.

While these types of beams are more efficient, something we value very highly at Garrett's Bridges, they are also harder to make. But the reward can be worth it. You can see an example of an L Beam in the Fernbank Bridge. We also have an example of an I Beam Bridge, and a bridge that uses a T Beam.

Truss

Here at Garrett's Bridges, we love the Truss Bridge. Most of the model bridges you will find here are truss bridges. We dedicate quite a bit of web space to analyzing Truss Design and how to customize a truss to fit your needs. Truss bridges are fun because it is easy to analyze them using the Method of Joints, or by using a program such as the Bridge Designer from Jonhs Hopkins University.

Arch

Arch bridges are beautiful, and effective. In real life their effectiveness has a limited range, meaning they are limited in effective length. How Stuff Works does a pretty good job explaining Arch Bridges.

Cantilever

The Cantilever is a very interesting concept. It supports the weight with a counter weight on one end. This photo is perhaps the most famous for demonstrating how this type of bridge works:

The problem with using a Cantilever (as well as Suspension and Cable Stayed bridges) is that they need to be anchored down to something. Real bridges are anchored to the ground using concrete abutments. Model bridge makers do not have that option. Most model bridges need to be portable, which means you can pick them up and plop them down in another spot. We don't know of any model cantilever bridges. If you do, please share by leaving a comment at the end of this post.

Wikipedia has a pretty good article on the Cantilever Bridge.

Suspension

Suspension bridges are some of the most beautiful structures known to mankind. Their elegant curved cables. Not only are they nice to look at, but they allow engineers to design longer spans than any other type (with the exception of Cable Stayed). Suspension bridges work by using their main cables to transfer weight from anywhere on the bridge, over the top of the towers, down to the anchor points at each end of the bridge. This is quite effective.

It is rather difficult to make a functional model suspension bridge. But we have a couple examples: Suspension Bridges

Cable Stayed

Cable Stayed bridges are similar in concept to suspension bridges, and thus are sometimes lumped together with them. However, they differ in that there is not one continuous cable that stretches from one end of the bridge to the other. Instead, it uses its towers as a focal point with cables going down to the deck on both sides in straight lines. Unlike a suspension bridge where the main cable is not tight, the cables on a 'Stayed bridge are very taut. Here is a page from PBS that explains Cable Stayed bridges in more detail.

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Building model bridges is fun. So fun that sometimes you might not even know you are learning. Physics, math, and engineering concepts are brought to life through the hands-on project of designing and building a model bridge. Garrett's Bridges is a resource used by teachers, students, and parents alike for turning model bridge building into a fun and rich experience.

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This shows us how weight can be distributed in a unique way that allows heavy amounts of weight can be placed on something fragile.  The shape used here is a curve!

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The Science and Engineering Fair is a contest with two specific types of entries:

1. Science Fair Projects: The scientific method is used when designing and developing a science project.
2. Engineer Fair Projects: The engineering method are entries into a contest

In the diagram, science presenter, Dawn Shock is demonstrating the strength of dome-shaped egg shells. The weight of the books pushing down on top of the domed-shaped eggs doesn't push straight down, instead, the weight is distributed outward along the curve of the egg. This is called force distribution.

The egg shell experiment provides research information that could be used in designing a science project or an engineering project. Discover for yourself :
Testing the Strength of Egg Shells
When deciding on developing a science project or an engineering project, first check out:
Scientific Method vs. Engineering Method
Next, study the criteria used to evaluate these two different kinds of projects:
How Science and Engineer Projects Are Evaluated.

Fun Fact: Thomas Alva Edison was a very precocious (unusual early development) child. One of his earliest experiments demonstrated his curiosity about the world around him. Tom saw a mother hen sitting on eggs and was told that she was keeping her eggs warm so that they would hatch. Being gone for a time, his sister was sent to find him. She discovered young Tom sitting on a nest of eggs. He was warming the eggs so that they would hatch.

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The Science and Engineering Fair is a contest with two specific types of entries: 1. Science Fair Projects: The scientific method is used when designing and developing a science project. 2. Engineer Fair Projects: The engineering method are entries into a contest In the diagram, science presenter, Dawn Shock is demonstrating the strength of dome-shaped egg shells.

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To make a good marshmallow tower you need to use geometric shapes because this causes the tower to become more sturdy when the weight is evened out.

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One fun science or team building activity is building a marshmallow tower, with a prize for the group or individual who builds the tallest tower. Generally the rules of such tower-building exercises specify the number and size of marshmallows contestants can use, and some kind of straight material used between the marshmallows such as spaghetti or toothpicks.

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Triangle towers are best for building stabe and high towers.

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People tend to worry about being in tall buildings during an earthquake, often without good reason, providing they're built to contemporary quality standards, says seismology expert Gary C. Hart. .

"I'd love to be in one of the Century Plaza towers in Century City during an earthquake, enjoying the ride and feeling quite safe," says the president of Englekirk & Hart Inc., a Los Angeles-based firm of consulting engineers.

He added that, while the 44-storied twin landmark structures do not have a monopoly on earthquake worthiness, they are among the city's high-rise structures that have the right stuff to endure a stiff jolt.

Hart should know. He's been monitoring the 2029 and 2049 buildings on Century Park East for some time as part of the U.S. Geological Survey's monitoring team.

Increased Resistance

"The triangular shape and engineering of those buildings will cause them to sway less during an earthquake than a rectangular building because they offer increased resistance to twisting--often the cause of major damage during a severe earthquake," he said.

The towers, completed in the mid-1970s, are among several hundred structures that serve as full-scale seismic laboratories for the Geological Survey, Hart said. He noted that the federal approach to structural seismic monitoring differs from the state's approach in that Survey's primary interest is in buildings of unusual or unique design, so that they may be studied as research models.

"The federal government's objective is long-range research. Its efforts focus on learning more about how to design buildings from the data collected here and in other earthquake-prone areas," Hart said.

Through his 20-year affiliation with UCLA, as a professor of civil engineering specializing in seismic design of buildings, Hart has been a member of monitoring teams on numerous structures both for the Survey and for the state.

"USGS's continuing program to evaluate the dynamic properties of structures (especially those with novel design features)," Hart said, "has included on-going tests of both forced vibration and ambient vibration on the Century City South Tower building.

"The results for dynamic behavior of the multistory triangular-shaped buildings have been quite favorable, according to a report delivered by the Earthquake Engineering Research Center at UC Berkeley for the National Science Foundation."

Rising 44 stories, the steel-frame towers face each other at the apex (resembling a bow-tie from the air). At the time they were built they were the world's only twin triangular towers.

Theme Structures

Architect Minoru Yamasaki's concept of equilateral triangles (each side 260 feet wide), as dominant theme structures for Century City, were intended to contrast the curved facade of the Century Plaza Hotel, which Yamasaki also designed.

The triangle, Hart noted, has an excellent configuration for support and strength because its three bases are spread out in fairly equal proportions around its central core.

Yamasaki's use of concentric triangular service cores for the buildings created space that was conventional and rectangular, except for its unusual corner offices.

Samuel H. Kaufman, building manager for the towers, couldn't be more delighted with the selection of the twin buildings by the U.S. Geological Survey among its study sites in the Los Angeles area.

Special Equipment

"They installed special monitoring equipment (paid for by the National Science Foundation) during final stages of construction of the towers in 1976 and 1977.

"And we were pleased to learn that the equipment registered little or no motion to the buildings during our major earthquake of Oct. 1, 1987," Kaufman said.

His management team is currently implementing a $200,000 program to reinforce the electrical and other service systems to bring them up to the latest seismic safety technology.

"When we complete the work, our systems will have been upgraded to the modern design criteria set for hospitals, police and fire stations."

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Triangular Towers Get High Marks for Earthquake Safety

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People tend to worry about being in tall buildings during an earthquake, often without good reason, providing they're built to contemporary quality standards, says seismology expert Gary C. Hart. . "I'd love to be in one of the Century Plaza towers in Century City during an earthquake, enjoying the ride and feeling quite safe," says the president of Englekirk & Hart Inc., a Los Angeles-based firm of consulting engineers.

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This website shows how Romans used arches to create even weight distribution and make a strong tower.

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This picture shows that multiple bases can improve the balance of the structure so you can have more of a reliable base that can hold up the marshmallow.

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How shapes can be self reinforcing, by using its points of structure to hold itself up.

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Summary Students are introduced to brainstorming and the design process in problem solving as it relates to engineering. They perform an activity to develop and understand problem solving with an emphasis on learning from history. Using only paper, straws, tape and paper clips, they create structures that can support the weight of at least one textbook. In their first attempts to build the structures, they build whatever comes to mind. For the second trial, they examine examples of successful buildings from history and try again.
This engineering curriculum meets Next Generation Science Standards (NGSS).

Engineering Connection

Engineers are presented with new challenges every day. At first, many of these problems may seem impossible to solve. To find a solution, engineers use problem-solving techniques and brainstorm as many creative ideas as possible. What seems impossible at first becomes possible through the use of teamwork, the engineering design process and learning from past successes and failures.

Learning Objectives

After this activity, students should be able to:

Explain how engineers use history to guide their designs.

Demonstrate problem-solving techniques such as brainstorming and the engineering design process.

Explain that different shapes have different strengths.

Realize that triangles are the strongest shape and recognize that they can be found in most structures.

Educational Standards

Each TeachEngineering lesson or activity is correlated to one or more K-12 science, technology, engineering or math (STEM) educational standards.

All 100,000+ K-12 STEM standards covered in TeachEngineering are collected, maintained and packaged by the Achievement Standards Network (ASN), a project of D2L (www.achievementstandards.org).

In the ASN, standards are hierarchically structured: first by source; e.g., by state; within source by type; e.g., science or mathematics; within type by subtype, then by grade, etc.

NGSS Performance Expectation

Click to view other curriculum aligned to this Performance Expectation

This activity focuses on the following Three Dimensional Learning aspects of NGSS:

Science & Engineering Practices

Disciplinary Core Ideas

Crosscutting Concepts

Plan and conduct an investigation collaboratively to produce data to serve as the basis for evidence, using fair tests in which variables are controlled and the number of trials considered. Make observations and/or measurements to produce data to serve as the basis for evidence for an explanation of a phenomenon or test a design solution.

Tests are often designed to identify failure points or difficulties, which suggest the elements of the design that need to be improved. Different solutions need to be tested in order to determine which of them best solves the problem, given the criteria and the constraints.

Suggest an alignment not listed above

Materials List

For each group:

10 sheets of copy paper (okay if has printing on it, such as paper from recycle bin)

roll masking tape

20 drinking straws

20 paper clips

2-3 pre-weighed hard cover books (give each group similarly weighted books)

scissors

For the class to share:

small scale for weighing textbooks

For class demonstration by teacher:

7 tongue depressors or Popsicle sticks

7 large brads

Worksheets and Attachments
Visit [www.teachengineering.org/activities/view/cub_intro_lesson01_activity1] to print or download.

Introduction/Motivation

Engineers are constantly being challenged to solve the world's new and complicated problems. Many of these problems initially seem impossible to solve, but engineers find a way to make things happen! In the 20th century, engineers developed previously unimaginable things such as electricity, mass transportation, thousands of different automobiles, and even space travel. Engineers often look back in history to learn from past engineering successes and failures as they design and build amazing new things. Every day, engineers are thinking of ways to improve on what already exists as well as developing brand new ideas that have never been created before. In 2003, the tallest building in the world, the Taipei 101, was completed (see Figure 1). Located in Taiwan, the Taipei 101-named for its 101 floors-stands at 1,671 feet, more than a quarter mile tall! For engineers to come up with a plan for this building (and other similarly challenging structures), they must be creative and think "outside the box."

Let's talk about buildings. What makes a building strong? (If students give answers regarding the materials used [concrete, steel, wood, etc.], continue to ask questions leading them towards the idea of shapes.)] What else, besides the materials used, makes the building strong? Let's brainstorm some ideas. Consider the pyramids in Egypt. Those buildings are very strong and have lasted hundreds of years. They have a very distinctive shape that aids in their strength. Structures must be able to remain standing despite large amounts of force put on them by weight and other factors such as earthquakes or wind. Using different geometric shapes, structures are supported in different ways.

An example of a building using two different shapes, triangles and columns, is the Parthenon, a very successful engineering feat. The Parthenon began construction over two thousand years ago in 447 BC-at the height of the Athenian empire-and is still standing today (see Figure 2). The Parthenon was a temple built to represent the power and strength of the residents of Athens, Greece. This is an excellent example of a well-built structure that engineers can study, enabling them to learn better designs from the past for the future.

Now that we've brainstormed for a little while, let's begin our activity. Today you all are going to be engineers with a specific problem: you must build a structure to hold up as many books as possible using only the materials provided. To solve this problem, think like an engineer. As you work with your team, follow the engineering design process-be creative and think "outside of the box." Remember to keep in mind other things that make buildings strong, besides the materials. And, do not be deceived by using paper and straws to build a structure; paper is very strong when used to its best advantage! (Hint: think shapes; see Figure 3.)

Procedure

Before the Activity

1. Gather materials.

2. Collect hard cover books for testing. Weigh each book (if they are different sizes) so that students can calculate how much weight their structures support.

3. Make either overhead transparencies or handouts of the Design Process Overhead and Brainstorming Guidelines.

4. Make the square and triangle shapes using tongue depressors or Popsicle sticks and brads, as shown in Figure 2.

Draw a table on the board similar to the one below:

With the Students

Explain the design process to students and show them the design process handout/transparency. Have students define the problem and ask questions about what they need to know to answer the problem. Explain the importance of brainstorming and the suggested guidelines.

Rule 1: Postpone and withhold your judgment of ideas.

Rule 2: Encourage wild and exaggerated ideas.

Rule 3: Quantity of ideas counts at this stage-not quality.

Rule 4: Build on the ideas put forward by others.

Rule 5: Every person and every idea has equal worth.

1. Direct students to use the materials to build structures able to hold a book 1.5"-2" off the ground. Explain that they get 1 minute to decide how to build the structures, 8 minutes to build and then 2 minutes to test, so be ready to work quickly.

2. Divide the class into groups of three students each.

3. Give each team 10 pieces of paper, 10 straws, 1 roll of masking tape and 10 paper clips.

4. Begin timing 1 minute for students to discuss their ideas-remind them that this is the time to use their brainstorming skills.

5. When time is up, tell them to begin building. Time 8 minutes for students to build.

6. After 8 minutes, stop them and begin testing for 2 minutes. Have students calculate the total weight their structures supported (based on the weight of the pre-weighed books they were able to support before the structures failed).

7. Have the students record how much weight their structures supported in the table on the classroom board.

8. After the first test, ask students if they were successful. (It is unlikely that students find a solution after the first try.) Review with students what they tried, what worked and what did not work. Ask the class what they think engineers do when they are having a hard time solving a problem. (Lead them towards the ideas of using their knowledge of math and science as well as looking at what has worked in the past.)

9. Have students think about different geometric shapes and brainstorm which are the strongest.

10. Show students prepared shapes made from tongue depressors and brads. Show them how a square deforms under pressure whereas a triangle does not. Show them that by reinforcing a square or rectangle with a diagonal support (making 2 triangles) the new shape is much stronger.

11. Encourage students to try building columns and triangles. Explain that triangles are the strongest shape and can be found in most structures. Brainstorm as a class how to make the structures they are building stronger using their new knowledge of the strength of shapes.

12. Give students a second try at re-designing and re-building their structures with their existing materials. Again, provide 1 minute to discuss ideas, 8 minutes to build, and 2 minutes to test.

13. Ask students if their structures worked this time. What did they do differently? How did looking to past engineering projects help them?

14. Have students record the number of books their structures held in the second trial on the classroom board table.

15. Ask students to share their design ideas with the class. As a class, discuss how learning from history and knowing more about the strength of shapes helped them build improved structures the second time.

Assessment

Pre-Activity Assessment

Discussion Questions: Solicit, integrate and summarize student responses.

Why would an engineer want to learn about history? What could an engineer learn from history that would help them create a good design? (Answer: Engineers study history to learn about past engineering successes and failures, which helps give them ideas of things to try and/or avoid in their new designs.)

Why is brainstorming important? (Answer: It helps us gather ideas from everyone in the team, allowing the team to come up with creative ideas.)

Activity Embedded Assessment

Design Process: Before the re-design, ask the students to write out the design process for their designs. What is the need? How is the problem defined? If the students are having trouble, do the first few steps with the whole class.

Re-Design Practice: Have the students list any design or fabrication changes they would make to the structures. Have them consider buildings and structures they see in their everyday life. Are there any similar characteristics shared by the different buildings? (Encourage the students to think about triangles and pillars/columns.)

Post-Activity Assessment

Presentation: Have the students give a short 1-2 minute presentation about their design to the class. In the presentation, ask them to explain some of the cool features of their projects and show which shapes they used to make their structure strong. Have them tell the class how many books their structures were able to hold and describe the failure mode of their designs. (Figure 5 shows the three types of failure modes. Most structures fail by buckling and a few by compression.) Have them give a few ideas of how they could make their structure even stronger (i.e., by adding more columns, thicker columns or triangles).

Discussion: Talk as a class about some of the ideas that could be used to make the structures stronger. Show some pictures of buildings that utilize the different (and strong) shapes. If you are doing this as part of the Introduction to Engineering unit on the Olympics, show examples from Athens, Turin, Beijing and other Olympic cities to keep with the theme. A great U.S. example is the D.C. capitol building that uses pillars, triangles, arches and domes! As each group presents, a list compiled a list of their ideas, which the class may review once the presentations are finished.

Safety Issues

Use caution when cutting straws with scissors.

Troubleshooting Tips

If doing this activity as part of the Olympic Engineering unit, gear your examples towards the Olympics by showing pictures from Olympic sites and cities.

If part of a structure is carrying more weight than the rest, the structure will most likely fail faster and not be able to hold as much as when the structure is loaded evenly. Point out that how the structure is loaded with weight plays an important role in its success or failure.

If students get frustrated during the first attempt, shorten the building time.

If students do not find success on the second attempt, encourage them to learn from the design models of other successful groups. Ensure that they understand the relevance of different shapes and their strengths. If time allows, give the group the opportunity to build one last design after they understand the concepts.

Activity Extensions

Have students calculate how much taller the Taipei 101 tower is than their school building. (Answer: The average classroom is about 15 feet tall. 1671/15 = 111.4 times taller.) Then figure out how many fourth-grade students it would take standing on each other's shoulders to reach the top of the Taipei 101 Tower. (Answer: Take the average height of the class and divide into 1671 to see how many students it would take to reach 1,671 feet tall.)

Have the students think of other shapes that appear in structures. What about arches and domes? Or more simple shapes like octagons and hexagons? Which shape do they think is the strongest? Have the students build and test their own shapes.

Have the students research structural engineers and create a list of five projects they might have worked on.

Activity Scaling

For younger students, give them more time to brainstorm and build.

For older students, reduce the time to build and have them make a longer, more in-depth presentation.

For more advanced students, challenge them to make a structure that can support a student standing on a textbook (see Figure 3). Have a class competition to see which team can create a structure that holds the most weight.

References

Taipei 101, Understanding Health Cities. 2005 Taipei City Government. Accessed October 17, 2006. english.taipei.gov.tw/MP_100002.html

Contributors Tod Sullivan; Melissa Straten; Katherine Beggs; Denali Lander; Abigail Watrous; Janet Yowell

Copyright © 2006 by Regents of the University of Colorado.

Supporting Program Integrated Teaching and Learning Program and Laboratory, University of Colorado Boulder

Acknowledgements

This digital library curriculum was developed under grants from the Fund for the Improvement of Postsecondary Education (FIPSE), U.S. Department of Education, and National Science Foundation (GK-12 grant no. 0338326). However, these contents do not necessarily represent the policies of the Department of Education or National Science Foundation, and you should not assume endorsement by the federal government.

Last modified: August 10, 2019

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History and Testing Shapes of Strength for Buildings - Activity

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Students are introduced to brainstorming and the design process in problem solving as it relates to engineering. They perform an activity to develop and understand problem solving with an emphasis on learning from history. Using only paper, straws, tape and paper clips, they create structures that can support the weight of at least one textbook.

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By replacing the marshmallows with tape and balancing 2 or 3 pyramids on top of each other, the weight would be distributed and the marshmallow would balance.
Group 4 Period 1

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Master the secret of building a REALLY tall spaghetti and marshmallow tower.

A surprisingly useful life skill, considering the current popularity of spaghetti and marshmallow towers at school science days and work team building events.

And while it's not rocket science, it's trickier than you think... so read the tips below to ensure your tower stands tall and proud...

Step by step guide

If you do want to build a TALL tower, it does require some planning. Hopefully the following guide will point you in the right direction.

STEP 1: Start by building pyramids with four marshmallows at the base and one at the top. Use 1/2 length strands of spaghetti to connect the base and full length strands to connect the base to the marshmallow at the top.

And remember, always push the spaghetti deep into the marshmallow, it provides more grip (B).

STEP 2: Next, take two completed pyramids and join them together with a 'bottomless' pyramid.

STEP 3: Connect the bases of the two pyramids with two strands of spaghetti.

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STEP 4: Continue joining pyramids until you have three rows, each consisting of four pyramids.

STEP 5: Connect the tops of the pyramids with horizontal lengths of spaghetti to complete the first layer.

STEP 6: Build a second layer of pyramids on top of the first layer, this one will consist of two rows of three pyramids.

Note: For layer 3 we have to change tack, because if it were another row of pyramids it would consist of only two pyramids!

STEP 7: Start by connecting the six marshmallows at the top of layer 2 to four marshmallows in square formation. Add lots of diagonal cross braces to provide extra rigidty.

STEP 8: Construct two 'flying buttresses' on opposite sides, each made from a single marshmallow supported by spaghetti, this will help support the spire.

STEP 9: To make the spire connect three cubes, with a base the same size as the four marshmallows in layer 3. Add DIAGONAL cross braces to each side, and across OPPOSITE sides, otherwise the cubes will collapse.

STEP 10: Add two more flying buttresses, the mirror opposite to the ones you added to layer 3.

STEP 11: To complete the spire add a 'bottomless pyramid' onto the top cube, to give the spire a nice point!

STEP 12: Building the spire separately means you can more easily move or transport your tower. When you are ready to join them, lower the spire onto the base so the 'flying buttresses' are aligned.

STEP 13: Fix them together by pushing short strands of spaghetti through both marshmallows in each 'flying buttress'.

STEP 14: Spaghetti and marshmallow tower challenges often require an egg to be supported by the structure. The best way to do that is by creating a 'nest' from short strands of spaghetti pushed into the top marshmallow.

Materials

What will I learn?

1) Sometimes the best way to learn about science is not through maths and formulas but by playing with materials*.

2) Simple techniques and rules when repeated at scale can create very impressive and complex structures.

3) Making projects with edible materials (especially those of the sweet variety) are particularly popular with kids!
*But don't tell your maths teacher that!
Give It Your Own Twist

Building a spaghetti and marshmallow tower doesn't have to be the preserve of school science projects, it also makes a great kids' activity for rainy days and summer holidays!

Too lazy to drive to the shops?

Here's links to spaghetti and marshallows on Amazon.

Have fun!

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How to Build a TALL Spaghetti and Marshmallow Tower

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Master the secret of building a REALLY tall spaghetti and marshmallow tower. A surprisingly useful life skill, considering the current popularity of spaghetti and marshmallow towers at school science days and work team building events. And while it's not rocket science, it's trickier than you think...

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1. Geometric shapes
2. Strong base
3. equal measurements
Group 1 Period 1

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One fun science or team building activity is building a marshmallow tower, with a prize for the group or individual who builds the tallest tower. Generally the rules of such tower-building exercises specify the number and size of marshmallows contestants can use, and some kind of straight material used between the marshmallows such as spaghetti or toothpicks.

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P1 Group 2: Weight distribution in shapes 

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P1 Group 2: Weight distribution in shapes 

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group 2
This article teaches us about weight distribution in domes, triangles, and other important shapes to make our structure stronger

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Lesson Summary

Overview

In this activity, students study the various shapes engineers choose to make structures strong -- in particular, triangles, arches, and domes. They begin by experiencing firsthand the forces of tension and compression. Then they construct a variety of forms, test their strength, and discuss how tension and compression are distributed by triangles, arches, and domes. The multimedia resources used throughout the lesson show many applications of these shapes used in ancient and modern cultures. Students also discuss examples of these shapes that they have seen in their own experiences.

Objectives

understand that tension and compression are distributed by various shapes in architecture

discover that triangles provide strengthening ability for structures

discover that arches utilize compression to strengthen bridges and other structures

discover that arches and domes provide weight-bearing ability for structures

discuss examples they have seen of triangles, arches, and domes in architecture

Grade Level: 6-8

Suggested Time

Multimedia Resources

Use these resources to create a simple assessment or video-based assignment with the Lesson Builder tool on PBS LearningMedia.

Materials

Before the Lesson

Print copies of the handouts and activities listed under Materials for your students.

The Lesson

Part I: Compression and Tension

1. Have students work in pairs to experience compression for themselves. Tell student pairs to stand face to face and gently press their palms together at about shoulder height (as in a "high five"). Then tell them to slowly lean into each other. Ask them to describe what they feel, where they feel it, and what they think is causing the feeling.

2. Next, have students experience tension. While standing and facing each other, have student pairs grab hands and gently lean away from each other. Ask them to describe what they feel, where they feel it, and what they think is causing the feeling.

3. Show the Triangles and Arches in Architecture stills collage and discuss the following:

Which shapes provide strength to structures?

What shapes are used in buildings in your neighborhood? In large cities? In ancient buildings?

Is using certain shapes to increase the strength of structures a modern idea?

What architectural elements have carried through from ancient to modern cultures? What elements have changed? How do you think these shapes impact the designs that today's engineers and architects choose for buildings?

4. Distribute the Building Big: Straw Shapes handout, drinking straws, and paper clips. Have students work in groups if supplies are short or if you find that teamwork is productive in your class. After students have built their triangles and squares, ask them to identify the areas in each shape that experience tension and compression when a load is placed on top of the shape. Ask them to explain why the triangle is stronger than the square in terms of the distribution of tension and compression.

5. Show the Triangles: Designing a Newspaper Chair video and continue to discuss how triangles help distribute forces such as tension and compression under a load.

Part II: Arches

6. Review the Building Big: Human Arch Mini-Activity. Then break the class into groups of four or five students each to do the activity. Have students describe where they feel pushing (compression) and pulling (tension).

7. Show the Arch Bridge video. Discuss how the construction of an ancient arch relates to the forces the students experienced in their human arch. Have students explain why the shape of each rock and the keystone are so vital to the strength and stability of the arch.

8. Distribute the NOVA: Tasty Arch handout, cream wafers, plastic knives, and sandpaper. Have students work in teams to build arches per the instructions. If time permits, have them test the strength of the arches under a load of books. Ask students to explain what forces are exerted on the arch when the book is on top, and how the arch distributes those forces.

Part III: Domes

9. Review the Building Big: Human Dome Mini-Activity. Then break the class into groups of 10 students each to do the activity. Have students explain how the dome shape distributes forces to be able to support a heavy load.

10. Show the Pantheon Dome video. Discuss how ancient cultures used certain shapes to support heavy loads. Have students explain where additional mass must be placed on a dome to increase support, and where mass can be removed to lighten the load.

11. Distribute the Triangles: Testing the Strength of a Gumdrop Dome handout (in English and/or Spanish), gumdrops, and toothpicks. Have students work alone or in teams to build domes per the instructions. If time permits, have students test the strength of the domes under a load of books. Ask students to explain what forces are exerted on the dome when the book is on top, and how the triangle shapes within the dome distribute those forces. If it is too difficult to balance a load of books on a single dome, have students devise a different method to test the strength of a dome. If making the domes is not feasible, have students watch the Triangles: Testing the Strength of a Gumdrop Dome video.

Check for Understanding

Have students discuss the following, using sketches and arrows wherever possible:

Explain the reasons why triangles, arches, and domes are used to increase the strength of structures. Give examples from the multimedia resources you have used.

Explain how the architectural lessons learned from ancient cultures have affected the engineering and construction of today's buildings.

Have students draw a triangle, an arch, and a dome. Tell them to use arrows to show the direction of tension and compression when a load is placed on top of each shape.

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In this activity, students study the various shapes engineers choose to make structures strong -- in particular, triangles, arches, and domes. They begin by experiencing firsthand the forces of tension and compression. Then they construct a variety of forms, test their strength, and discuss how tension and compression are distributed by triangles, arches, and domes.

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P1 Group 3: Force Distribution in shapes.

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P1 Group 3: Force Distribution in shapes.

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Group 3 Period 1:
A triangle is the best shape for distributing weight because the more weight you put on top, the more the sides will compress and create more stability.

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A tower that uses more spaghetti sticks on the bottom helps make the support and balance better, because just a long vertical 1 spaghetti thin tower will not give support and may fall.

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Let's just say that day two of year two was amazing! The $2.95 I spent on supplies for this activity was money well-spent! When my students entered the classroom, they saw this message on the Smart Board.

Of course, they instantly wanted to know what The Marshmallow Challenge was. Even more than that, they wanted to know if they got to eat marshmallows...

I used the following slide to explain the rules:

I learned about The Marshmallow Challenge from watching this TED Talk. The premise is simple. In groups of four, students are given 18 minutes to construct the tallest tower possible using 20 sticks of spaghetti, 1 yard tape, 1 yard string. The tower must be freestanding, and it must support a marshmallow. The marshmallow must be the highest point on the structure.

I had so much fun just walking around and eavesdropping on the conversations that ensued as students discussed the best way to build their towers. I liked that there was a clearly defined time limit because it forced my students to really focus.

And before I share with you the results, I have to tell you about what I learned. Some people eat dry spaghetti. I fully expected my students to ask to eat the extra marshmallows. But spaghetti?

Here are some of the results:

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Let's just say that day two of year two was amazing! The $2.95 I spent on supplies for this activity was money well-spent! When my students entered the classroom, they saw this message on the Smart Board. Of course, they instantly wanted to know what The Marshmallow Challenge was.

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1.)NASA describes a spaghetti tower challenge and then goes on to describe the physics behind it.
2.)The article talks about geometrical shapes and force distribution throughout three-dimensional shapes. This article is specifically directed towards 5th-8th graders
3.)Group 6, Period 1

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This shows how to create a strong structure that resembles the Eiffel Tower.
Posted by: Group 7

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Be sure to include:
1. A descriptive title of what you are sharing.
2. A short summary of why it is helpful or what somebody should look at when viewing your resource.
3. Your group number and period.

Be sure your contribution is unique!

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Try some of these search terms when conducting your research:
"Pasta Tower"
"Spaghetti Tower"
"Marshmallow Challenge"
"Best Shapes for a Tower"
"Force distribution in shapes"
"Forces in towers

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These are helpful in seeing how the original challenge is set up...
Posted by: Mr. S