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The Roles of Water in Earths Surface Process

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The Roles of Water in Earths Surface Process

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The resource describes the water cycle, and expands that basic information to include other ways water is key to life on earth.

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In this video Paul Andersen explains the vital role that water plays in the processes on the Earth's surface. Water has several unique properties including high heat capacity, transparency, polarity and the ability to change the chemical behavior of the mantle. The Earth is largely a water planet but most of the water is found in the oceans or locked in ice. Water is a powerful erosive force on the planet. A K-12 teaching progression is also included.

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ESS2.C: The Roles of Water in Earth's Surface Processes - The Wonder of Science

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In this video Paul Andersen explains the vital role that water plays in the processes on the Earth's surface. Water has several unique properties including high heat capacity, transparency, polarity and the ability to change the chemical behavior of the mantle. The Earth is large

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A video view of a volcanic eruption as viewed from the ISS

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This is a volcano as viewed from the International Space Station.

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Let’s Get it Started - Growing a Garden from our Food?!?!

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Let’s Get it Started - Growing a Garden from our Food?!?!

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The information covers growing food from seeds, but my interest was cause and effect which asked the question, why do some seeds grow and others not.

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Welcome to the Virtual Science Education blog post. People are sending children PDF packets and online videos and calling that science. We prefer actually doing science with, well, anybody - your children, your parents, your neighbors, your friends, or for some stimulating individual time - to explore the world around you and think about science together.

What can we do at home to have fun with science?

Children love talking and reading science with people in their community. Often they are not only excited by the world around them but bursting with questions about the things they see that just don't seem to make sense just yet. With the potential for students to be learning virtually or just spending more time at home, there is a need for parents to be able to find high quality and engaging science resources to stimulate and encourage learning at home.

But science is more than facts that old people figured out a long time ago and put into books - science is exploring and asking questions and being wrong and...having fun. So, let's think about one possible way to bring real science home.

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Virtual Sci Ed - Science is For Everyone - Phenomena for NGSS

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Spring has started, but most of us are social distancing away at home. While inside, how can we explore the world of seeds - and maybe even extend the life of the fruits and vegetables we already have?!?

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This resource made connections to plant growth, photosynthesis, and how/why young sunflowers move to follow the sun.

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Description: This is an excellent phenomenon that can be used in many different units. According to researchers only young sunflowers will follow the Sun. These flowers are following a natural circadian rhythm to receive the most light for photosynthesis. However when they mature the flowers will mainly face east. The reason for this is fairly simple, bees like warm flowers, and the flowers facing the east are the warmest.

Web Resources: The Mystery Of Why Sunflowers Turn To Follow The Sun - Solved - NPR, Helianthus - Wikipedia

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Why Do Sunflowers Follow the Sun? - The Wonder of Science

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Description: This is an excellent phenomenon that can be used in many different units. According to researchers only young sunflowers will follow the Sun. These flowers are following a natural circadian rhythm to receive the most light for photosynthesis. However when they mature the flow

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This collection of information includes lesson plans and videos before, during, and after the 1980 eruption.

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St. Helens: Out of the Ash | The Volcanic Eruption of Mount St. Helens | PBS LearningMedia

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In May of 1980 Mount St. Helens grabbed the world’s attention by putting on a volcanic display never before witnessed in modern times. Today, it still fascinates millions. People from around the globe are drawn to the Mount St. Helens National Volcanic Monument. KSPS’s St. Helens: Out of the Ash provides eyewitness accounts of the volcanic eruption at Moutn St. Helens and explores the effects of the eruption and the changes that have occurred to the mountain and its surrounding areas ever since. Teach students vocabulary related to volcanoes, the different types and features of volcanoes, and the geological and societal effects of volcanic eruptions with these video segments and accompanying learning gudie. Visit KSPS Education for additional educator resources.

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This grouping of videos and lessons provides support for how things grow, or don’t, and how food is available.

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This engaging KET-produced video collection helps teach elementary students about the art and science of growing food, with an emphasis on biological and environmental concepts. It also addresses topics related to nutrition and economics.

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This virtual field trip link gives students connection to the real world based on lessons presented in class.  It provides information about a variety of ecosystems with written and video information.

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Biosphere 2 Rainforest Virtual Field Trip | The Arizona Collection | PBS LearningMedia

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This virtual field trip is an interactive, deep-dive into the Biosphere 2 Rainforest.
Developed for middle school students, the virtual field trip provides an opportunity for individuals of all ages to explore the Rainforest biome in-depth while also learning more about climate change research,environmental challenges, and science concepts such as photosynthesis, carbon cycle, drought, the effects of temperature changes, and biodiversity. Biosphere 2 is uniquely positioned to conduct experiments that can be done in a simulated setting. As such, students will explore concepts that help forge connections to the real world.

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This interactive page will provide students with both basic and extended information regarding the water cycle.  It would be great to use for students at all levels as it provides written and video.

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Gross Science | Can Bird Poop Make Clouds? Third party materials: Flickr/Ingrid Taylor, Wikimedia Commons/Mrmariokartguy, Wikimedia Commons/J.R. Mann, Flickr/Jennifer Boyer, Flickr/Gary Bembridge, Wikimedia Commons/Henning Allmers, halmers@uos.de, Freesound/StateAardvark (used with permission from author), Freesound/Corsica_S, Freesound/joedeshon, Freesound/bennychico11.

©2017 WGBH Educational Foundation. All Rights Reserved.

Evapotranspiration - Video

NASA/Goddard Space Flight Center Conceptual Image Lab

Music: AndrewWeiss/Pond5

Evaporation - Video

NASA/Goddard Space Flight Center Scientific Visualization Studio. The topographic data used in the video are unpublished but courtesy of Ian Howat, The Ohio State University, Columbus, OH. The MOG mosaic (MODIS) is courtesy of T. Scambos, NSDIC, Bouder, CO. The Blue Marble data is courtesy of Reto Stockli (NASA/GSFC).

Precipitation - Video

NASA's Scientific Visualization Studio

Transport - Video

Scientific Visualization Studio The Blue Marble data is courtesy of Reto Stockli (NASA/GSFC).

Music: Story Of A New by Figure and Groove Productions.

Rivers & lakes - Video

NASA's Scientific Visualization Studio

Music: Story Of A New by Figure and Groove Productions.

Groundwater - Image

The Groundwater Foundation.

Surface runoff - Image

J.J. Gouin/Shutterstock

Hydrothermal vents - Image

NOAA

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This game is designed to reinforce the parts of various food chains.  I would use it to demonstrate how drought or flood would impact the chain.

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Food Chain Game - Science - Sheppard Software Educational Games for kids

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Food Chain Game - Food chains come to life: when a chain is correctly put together, it turns into an animated working chain!

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Story board reviews real life situation in North Dakota with storms damaging crops.

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This story map requires JavaScript, but running JavaScript is not currently allowed by your web browser. If you wish to view this story, please enable JavaScript in this browser or try a different browser.

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This story map requires JavaScript, but running JavaScript is not currently allowed by your web browser. If you wish to view this story, please enable JavaScript in this browser or try a different browser.

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A story map of various US locations that have experienced too much or too little rainfall.

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This story map requires JavaScript, but running JavaScript is not currently allowed by your web browser. If you wish to view this story, please enable JavaScript in this browser or try a different browser.

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This story map requires JavaScript, but running JavaScript is not currently allowed by your web browser. If you wish to view this story, please enable JavaScript in this browser or try a different browser.

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Students use dice to help them move and track their movements through the water cycle.

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This activity allows students practical experience with how various types of “earth” absorb water,

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Videos of drought data over time, US, world and projections to the year 2095.

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Drought Data and Projections | PBS LearningMedia

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See maps of drought data for the United States (2010–2018) and the world (2013–2018) as well as maps of U.S. drought risk projections until 2095. Use this resource to observe seasonal patterns and identify the drought risk for different areas.

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This activity will allow students to design solar hot water heaters.  This would reinforce lessons on off grid living.

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Robotic Space Exploration - www.jpl.nasa.gov

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Creating an edible intrusive magma snack.  An experiment that allows students to see something that is otherwise underground and not easily viewed.

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This sweet simulation models geologic processes and features that are not easily observable, since they generally take place underground and over a long period of time.

The gelatin inside the cup represents the native country rock, the "geology" that happens to already be there. The sauce, pudding, or yogurt used represents the magma-molten rock, the source of igneous rock. The syringe represents a magma chamber, a large, hot, deep source of magma. Click to enlarge a diagram of volcanism below.

Volcanism (source: USGS)

Magma chambers can be located tens of kilometers underground. They exist near subduction zones, hot spots, rift valleys, and other areas of tectonic activity where the movement of tectonic plates can create fractures in the rock that create paths for magma to move upwards. In this Snack, as you force the "magma" to rise, it intrudes into the gelatin-the country rock. You might notice a big blob of sauce or pudding form. This is analogous to large bodies of magma known as plutons, which can be tens of kilometers wide. Multiple plutons that coalesce together are known as a batholith.

Sierra Nevada (source: NPS)

Plutons that remain underground and cool over long periods of time become intrusive igneous rock and can form the heart of large landmasses, and even mountain ranges. The Sierra Nevada Mountains in California (shown in the photo above) are an example of granitic plutons that formed underground about 100 million years ago and were exposed over time through erosion. The Sierra batholith forms the core of a mountain chain almost 650 kilometers long.

As your magma sauce forces its way through the gelatin, it can also create planar features, such as sills (intrusions that run parallel to country rock strata) and dikes (intrusions that cut across strata), as shown in the photos below.

Example of a dike (photo credit: Eric Muller)

Sometimes, a piece of gelatin will break off and can be seen embedded in the injected sauce. This is analagous to an inclusion of country rock suspended in cooled intrusive rock. These torn-off bits of rock are known as xenoliths.

When your magma sauce pierces the surface or erupts, it changes from intrusive to extrusive. Extrusive magma-that is, magma that has reached the surface-is called lava. Depending on its viscosity and quantity, lava can flow out smoothly or be ejected explosively, forming volcanic structures like those in Hawaii (made of basalt) or the Pacific Northwest (andesite and dacite), as shown in the photos below.

Hawaii (source: NPS)

Pacific Northwest (source: USGS)

As you eat your gelatin snack, you are effectively weathering and eroding your simulated rocks, removing surface layers and exposing the geologic formations beneath.

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This sweet simulation models geologic processes and features that are not easily observable, since they generally take place underground and over a long period of time. The gelatin inside the cup represents the native country rock, the "geology" that happens to already be there.

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Modeling the Ash Distribution of a Yellowstone Supereruption

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Modeling the Ash Distribution of a Yellowstone Supereruption

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Predictions with images of how far and deep ash would move if Yellowstone erupts.

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Authors Larry G. Mastin, Alexa R. Van Eaton, Jacob B. Lowenstern

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Modeling the Ash Distribution of a Yellowstone Supereruption

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The topic of Yellowstone supereruptions (ones producing greater than one thousand cubic kilometers of volcanic debris) generates much interest, but also occasional confusion. Computer models can help clarify the reality of eruption impacts, and provide insight on past eruptions.

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Tacoma Narrows Bridge history - Bridge - Lessons from failure

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Tacoma Narrows Bridge history - Bridge - Lessons from failure

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This site explains how the bridge was designed, and how wind was not factored into the design, ultimately causing the collapse.

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Lessons from the failure of a great machine

How Galloping Gertie's collapse left us a lasting design legacy.

What's here?

The damage

Main cables
During the collapse, the main suspension cables were thrown violently side to side, twisted, and tossed 100 feet into the air. They slipped from their positions in the cable saddles atop each tower. And, they fell hard on the approach spans. On the north cable at mid-span, where the cable band loosened, it broke more than 350 wires. Other wires were severely stressed and distorted. The main cables were a total loss, but salvage was undertaken. Their only value was as scrap metal.

Suspender cables
The violent collapse broke many suspender cables. Some were lost, some severely damaged, and some undamaged. Their only value now was as scrap metal.

Towers
The main towers (West Tower, #4; and East Tower, #5), including the bracing struts, were twisted and bent. Stress beyond the elastic limit of the metal resulted in buckling and permanent distortion. Their only value now was as scrap metal.

Deck-floor system
Not surprisingly, the concrete and steel of the center span that now lay on the bottom of the Narrows was deemed a total loss. The remainder of the broken concrete on the side spans needed removal. The floor system had sections that were bent and overstressed. Their only value now was as scrap metal.

Side spans
The loss of the center section, followed by the dropping of the side spans, caused substantial damage. The events stressed and distorted the plate girders and floor beams. Some buckled beyond repair.

Piers
Both the West Pier (#4) and the East Pier (#5) sustained no damage. The collapse of the center span caused partial sheering of rivets that attached the towers to the tops of the piers.

Anchorages
The anchorages for the main cables were undamaged. For building a replacement bridge, removal of part of the concrete would be necessary in order to spin the new main cables.

First investigations - Partial answers to "why"

The collapse of the 1940 Tacoma Narrows Bridge stunned everyone, especially engineers. How could the most "modern" suspension bridge, with the most advanced design, suffer catastrophic failure in a relatively light wind?

The State of Washington, the insurance companies, and the United States government appointed boards of experts to investigate the collapse of the Narrows Bridge. The Federal Works Administration (FWA) appointed a 3-member panel of top-ranking engineers: Othmar Amman, Dr. Theodore Von Karmen, and Glen B. Woodruff. Their report was the Administrator of the FWA, John Carmody and became known as the "Carmody Board" report.

In March 1941 the Carmody Board announced its findings. "Random action of turbulent wind" in general, said the report, caused the bridge to fail. This ambiguous explanation was the beginning of attempts to understand the complex phenomenon of wind-induced motion in suspension bridges. Three key points stood out:

(1) The principal cause of the 1940 Narrows Bridge's failure was its "excessive flexibility;"
(2) the solid plate girder and deck acted like an aerofoil, creating "drag" and "lift;"
(3) aerodynamic forces were little understood, and engineers needed to test suspension bridge designs using models in a wind tunnel.

"The fundamental weakness" of the Tacoma Narrows Bridge, said a summary article published in Engineering News Record, was its "great flexibility, vertically and in torsion." Several factors contributed to the excessive flexibility: The deck was too light. The deck was too shallow at 8 feet (a 1/350 ratio with the center span). The side spans were too long, compared with the length of the center span. The cables were anchored at too great a distance from the side spans. The width of the deck was extremely narrow compared with its center span length, an unprecedented ratio of 1 to 72.

The pivotal event in the bridge's collapse, said the Board, was the change from vertical waves to the destructive twisting, torsional motion. This event was associated with the slippage of the cable band on the north cable at mid-span. Normally, the main cables are of equal length where the mid-span cable band attaches them to the deck. When the band slipped, the north cable became separated into two segments of unequal length. The imbalance translated quickly to the thin, flexible plate girders, which twisted easily. Once the unbalanced motion began, progressive failure followed.

The investigation Board's most significant finding was simple and obvious: the engineering community must study and better understand aerodynamics in designing long suspension bridges.

Meanwhile, Professor F. B. Farquharson continued wind tunnel tests. He concluded that the "cumulative effected of undampened rhythmic forces" had produced "intense resonant oscillation." In other words, the bridge's lightness, combined with an accumulation of wind pressure on the 8-foot solid plate girder and deck, caused the bridge to fail.

Leon Moisseiff, who was contacted immediately after the failure, said he was "completely at a loss to explain the collapse." Moisseiff visited the ruined bridge one week later, touring under the watchful eye of Clark Eldridge. Moisseiff's design, while pushing beyond the boundaries of engineering practice, fully met the requirements of accepted theory at the time.

"Blind spot" - Design lessons of Gertie's failure

At the time the 1940 Narrows Bridge failed, the small community of suspension bridge engineers believed that lighter and narrower bridges were theoretically and functionally sound. In general, leading suspension bridge designers like David Steinman, Othmar Amman, and Leon Moisseiff determined the direction of the profession. Very few people were designing these huge civil works projects. The great bridges were extremely expensive. They presented immensely complicated problems of engineering and construction. The work was sharply limited by government regulation, various social concerns, and constant public scrutiny. A handful of talented engineers became pre-eminent. But, they had what has been called a "blind spot."

That "blind spot" was the root of the problem. According to bridge historian David P. Billington, at that time among suspension bridge engineers, "there seemed to be almost no recognition that wind created vertical movement at all."

The best suspension bridge designers in the 1930s believed that earlier failures had occurred because of heavy traffic loading and poor workmanship. Wind was not particularly important. Engineers viewed stiffening trusses as important for preventing sideways movement (lateral, or horizontal deflection) of the cables and the roadway. Such motion resulted from traffic loads and temperature changes, but had almost nothing to do with the wind.

This trend ran in virtual ignorance of the lessons of earlier times. Early suspension bridge failures resulted from light spans with very flexible decks that were vulnerable to wind (aerodynamic) forces. In the late 19th century engineers moved toward very stiff and heavy suspension bridges. John Roebling consciously designed the 1883 Brooklyn Bridge so that it would be stable against the stresses of wind. In the early 20th century, however, says David P. Billington, Roebling's "historical perspective seemed to have been replaced by a visual preference unrelated to structural engineering."

Just four months after Galloping Gertie failed, a professor of civil engineering at Columbia University, J. K. Finch, published an article in Engineering News-Record that summarized over a century of suspension bridge failures. In the article, titled "Wind Failures of Suspension Bridges or Evolution and Decay of the Stiffening Truss," Finch reminded engineers of some important history, as he reviewed the record of spans that had suffered from aerodynamic instability. Finch declared, "These long-forgotten difficulties with early suspension bridges, clearly show that while to modern engineers, the gyrations of the Tacoma bridge constituted something entirely new and strange, they were not new--they had simply been forgotten."

An entire generation of suspension bridge designer-engineers forgot the lessons of the 19th century. The last major suspension bridge failure had happened five decades earlier, when the Niagara-Clifton Bridge fell in 1889. And, in the 1930s, aerodynamic forces were not well understood at all.

"The entire profession shares in the responsibility," said David Steinman, the highly regarded suspension bridge designer. As experience with leading-edge suspension bridge designs gave engineers new knowledge, they had failed to relate it to aerodynamics and the dynamic effects of wind forces.

End of an era

The collapse of Galloping Gertie on November 7, 1940 revealed the limitations of the "deflection theory." Now, engineers no longer believed that suspension bridges needed to be stiffened only against the stress of moving vehicles and the "minor" effect of wind.

The failure of the Tacoma Narrows Bridge effectively ended Moisseiff's career. More importantly, it abruptly ended an entire generation of bridge engineering theory and practice, and the trend in designing increasingly flexible, light, and slender suspension spans.

Othmar Amman said of the collapse of the 1940 Narrows Bridge, "Regrettable as the Tacoma Narrows Bridge failure and other recent experiences are, they have given us invaluable information and have brought us closer to the safe and economical design of suspension bridges against wind action."

Suspension bridge design since 1940

"Mere size and proportion are not the outstanding merit of a bridge; a bridge should be handed down to posterity as a truly monumental structure which will cast credit on the aesthetic sense of present generations." - Othmar H. Amman, 1954

The end of the 1950s witnessed the construction of two of the greatest suspension bridges in the world, built by two of the 20th century's greatest bridge engineers. The Mackinac Strait Bridge, which opened in November 1957 in Michigan, was the crowning achievement of David B. Steinman. In New York the Verazzano-Narrows Bridge, designed by Othmar Amman, was 10 years in the making and finally opened in November 1964. Both of these monumental spans directly benefited from the legacies of the failed 1940 and the successful 1950 Tacoma Narrows Bridges.

Over the course of the last 60 years since Galloping Gertie failed, bridge engineers have created suspension bridges that are aerodynamically streamlined, or stiffened against torsional motion, or both.

Now, wind tunnel testing for aerodynamic effects on bridges is commonplace. In fact, the United States government requires that all bridges built with federal funds must first have their preliminary design subjected to wind tunnel analysis using a 3-dimensional model.

Failure of the 1940 Tacoma Narrows Bridge revealed for the first time limitations of the Deflection Theory. Since the Tacoma disaster, aerodynamic stability analysis has come to supplement the theory, but not replace it. The Deflection Theory remains an integral part of suspension bridge engineering. Today, the theory's principles serve as a model for the complex analytical methods (such as "Finite Element" computer programs) used by structural engineers to calculate stresses in the suspension Cable system.

Since the 1990s, advances in computer graphics technology and high-speed processing have enabled such calculations to be performed on desktop computers. Today, engineers recognize the importance of a thorough aerodynamic analysis of the structures they design. Advanced modeling software programs assist the complex calculations.

Why did Galloping Gertie collapse?

For over six decades, engineers have studied the collapse of the 1940 Tacoma Narrows Bridge. The experts disagree, at least on some aspects of the explanation. A definitive description that meets unanimous agreement has not been reached. The exact cause of the bridge's failure remains a mystery.

Why is it important to know the exact cause of the 1940 bridge's collapse? Engineers need to know how a new suspension bridge design will react to natural forces. The more complete their understanding, the better their problem solving, and thus, the stronger and safer their bridge. The fact that engineers still argue about the precise cause of the Galloping Gertie's collapse is testimony to the extraordinary complexity of natural phenomena. Today, the 1940 Tacoma Narrows Bridge's failure continues to advance the "scientific method."

The primary explanation of Galloping Gertie's failure is described as "torsional flutter." It will help to break this complicated series of events into several stages.

Here is a summary of the key points in the explanation.

1. In general, the 1940 Narrows Bridge had relatively little resistance to torsional (twisting) forces. That was because it had such a large depth-to-width ratio, 1 to 72. Gertie's long, narrow, and shallow stiffening girder made the structure extremely flexible.
2. On the morning of November 7, 1940 shortly after 10 a.m., a critical event occurred. The cable band at mid-span on the north cable slipped. This allowed the cable to separate into two unequal segments. That contributed to the change from vertical (up-and-down) to torsional (twisting) movement of the bridge deck.
3. Also contributing to the torsional motion of the bridge deck was "vortex shedding." In brief, vortex shedding occurred in the Narrows Bridge as follows:

(1) Wind separated as it struck the side of Galloping Gertie's deck, the 8-foot solid plate girder. A small amount twisting occurred in the bridge deck, because even steel is elastic and changes form under high stress.
(2) The twisting bridge deck caused the wind flow separation to increase. This formed a vortex, or swirling wind force, which further lifted and twisted the deck.
(3) The deck structure resisted this lifting and twisting. It had a natural tendency to return to its previous position. As it returned, its speed and direction matched the lifting force. In other words, it moved " in phase" with the vortex. Then, the wind reinforced that motion. This produced a "lock-on" event.

4. But, the external force of the wind alone was not sufficient to cause the severe twisting that led the Narrows Bridge to fail.
5. Now the deck movement went into "torsional flutter."

"Torsional flutter" is a complex mechanism. "Flutter" is a self-induced harmonic vibration pattern. This instability can grow to very large vibrations.

When the bridge movement changed from vertical to torsional oscillation, the structure absorbed more wind energy. The bridge deck's twisting motion began to control the wind vortex so the two were synchronized. The structure's twisting movements became self-generating. In other words, the forces acting on the bridge were no longer caused by wind. The bridge deck's own motion produced the forces. Engineers call this "self-excited" motion.

It was critical that the two types of instability, vortex shedding and torsional flutter, both occurred at relatively low wind speeds. Usually, vortex shedding occurs at relatively low wind speeds, like 25 to 35 mph, and torsional flutter at high wind speeds, like 100 mph. Because of Gertie's design, and relatively weak resistance to torsional forces, from the vortex shedding instability the bridge went right into "torsional flutter."

Now the bridge was beyond its natural ability to "damp out" the motion. Once the twisting movements began, they controlled the vortex forces. The torsional motion began small and built upon its own self-induced energy.

In other words, Galloping Gertie's twisting induced more twisting, then greater and greater twisting.

This increased beyond the bridge structure's strength to resist. Failure resulted.

What if...?

Sometimes it is fun and worthwhile to ask the question, "What if...?," about important historical events. Here's one with an answer that may surprise you.

What if Clark Eldridge's original design for the 1940 Tacoma Narrows Bridge had been built, instead of Leon Moisseiff's? Would it have blown down on November 7, 1940 like Galloping Gertie?

Answer: The bridge would still be there. That's the opinion of leading bridge engineers who have carefully studied Eldridge's design, with its 25-foot deep stiffening truss.

"I believe without a doubt," said one senior structural engineer, "that the bridge would have been aerodynamically stable for the wind speeds that destroyed Galloping Gertie."

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Tacoma Narrows Bridge history - Bridge - Lessons from failure

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How Galloping Gertie's collapse left us a lasting design legacy. Main cables During the collapse, the main suspension cables were thrown violently side to side, twisted, and tossed 100 feet into the air. They slipped from their positions in the cable saddles atop each tower. And, they fell hard on the approach spans.

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Tacoma Narrows Bridge history - Bridge - Lessons from failure

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Tacoma Narrows Bridge history - Bridge - Lessons from failure

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This site explains how the bridge was designed, and how wind was not factored into the design, ultimately causing the collapse.

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The purpose of this lab activity is to introduce the challenges of building a suspension bridge. Students will explore the engineering challenges of building the new Tacoma Narrows Bridge in 1950.

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An activity giving students practical experience building houses that may or may not survive storms.

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Tacoma Narrows Bridge Collapse "Galloping Gertie"

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Tacoma Narrows Bridge Collapse "Galloping Gertie"

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Video of the actual collapse of the Tacoma Narrows Bridge.

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Tacoma Narrows Bridge Collapse "Gallopin' Gertie"

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This interactive room design program allows students to design specific areas of a home, based on criteria and space limitations.

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Rooms is a collection of user-generated 3D spaces and a creative tapestry of quirky games, tranquil havens, and clever themes. Available for free on iPhone, iPad and desktop web.