Grade 3 Lesson 13 by Shahed Taha

Rounding two- and three-digit numbers to the nearest ten on the vertical number line

shahidtaha2018_ — 2023-12-06 14:43:54 UTC

Shahed Taha

EDUC 268D- PTR Lesson 3

Lesson Structure

shahidtaha2018_ — 2023-12-06 14:47:40 UTC

1) Objectives

2) Introduction

3) Application problems

4) Concept Development

5) Student Debrief/Wrap-Up

WHAT ARE YOU GOING TO LEARN?

shahidtaha2018_ — 2023-12-06 14:59:21 UTC

By the end of this lesson, students will be able to:

•Understand that rounding results in an approximate value.

•Round two-digit numbers to the nearest ten using a number line

•Round three-digit numbers to the nearest ten using a number line

Preliminary question

shahidtaha2018_ — 2023-12-06 15:01:22 UTC

The gum Sheila wanted to buy costs 26 cents. Should she give the cashier 20 cents or 30 cents?

DEFINE CONCEPTS

shahidtaha2018_ — 2023-12-06 15:04:02 UTC

Round

Rounding is a way to estimate or tell about how many

Rounding does not give an exact amount

Keywords

shahidtaha2018_ — 2023-12-06 15:06:19 UTC

Round up

To increase a number to the nearest ten above it

Round down

To decrease a number to the nearest ten below it

Keywords

shahidtaha2018_ — 2023-12-06 15:13:39 UTC

Less than

When one quantity is smaller than the other quantity

Greater than

When one quantity is more than the other quantity

Keywords

shahidtaha2018_ — 2023-12-06 15:15:16 UTC

Benchmark Numbers

Endpoints based on which other quantities can be estimated

Midpoint

A point at the exact middle of a line segment

Rename the Tens

shahidtaha2018_ — 2023-12-06 15:16:41 UTC

What is 9 tens= __

On your personal whiteboards, write what are:

10 tens=

20 tens=

80 tens=

Halfway on the Number Line

shahidtaha2018_ — 2023-12-06 15:20:40 UTC

130 and 140

830 and 840

560 and 570

shahidtaha2018_ — 2023-12-06 15:25:41 UTC

Problem 1: Round two-digit measurements to the nearest ten

shahidtaha2018_ — 2023-12-06 15:27:17 UTC

Let’s round 28 to the nearest ten

shahidtaha2018_ — 2023-12-06 15:28:21 UTC

When you look at your vertical number line, is 28 more than halfway or less than halfway between 20 and 30?

How did you know?

Plot it on the number line!

Problem 2: Round three-digit measurements of milliliters to the nearest ten

shahidtaha2018_ — 2023-12-06 15:29:04 UTC

Let’s round 17 milliliters to the nearest ten

Problem 2: Round three-digit measurements of milliliters to the nearest ten

shahidtaha2018_ — 2023-12-06 15:30:10 UTC

Let’s round 117 milliliters to the nearest ten

shahidtaha2018_ — 2023-12-06 15:30:57 UTC

When you look at your vertical number line, is 117 more than halfway or less than halfway between 110 and 120?

How did you know?

Plot it on the number line!

Round the measurements to the nearest ten

shahidtaha2018_ — 2023-12-06 15:31:42 UTC

75 mL

175 mL

Symbols

shahidtaha2018_ — 2023-12-06 15:32:44 UTC

≈

Approximate symbol

Equal symbol

Problem Sets/Individual Practice

shahidtaha2018_ — 2023-12-06 15:33:49 UTC

Solve lesson 13 problem set exercises 1 and 2 only

Make sure you use the RDW approach when solving

Wrap-Up

shahidtaha2018_ — 2023-12-06 15:35:55 UTC

Solve the exit ticket lesson 13

Do you have any questions?

shahidtaha2018_ — 2023-12-06 15:37:50 UTC