Algebra Readiness Made Easy Grade 4

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Stamp Stumpers

Overview

Presented with a set of stamps—some with geometric shapes and others with prices—

and its total cost, students figure out the price of each shape stamp.

Algebra

Solve equations with one variable • Replace symbols with their values •

Recognize that the same pictures have the same value • Understand that taking away

an addend changes the sum by the same amount

Problem-Solving Strategies

Reason deductively

Related Math Skills

Compute with whole numbers • Recognize chevrons, hexagons, octagons, pentagons,

squares, trapezoids, and triangles • Recognize cones, cubes, and cylinders

Math Language

Total cost • Geometric shapes: chevron, hexagon, octagon, pentagon, square,

trapezoid, triangle, cone, cube, cylinder

Introducing the Problem Set

Make photocopies of “Solve the Problem: Stamp Stumpers” (page 22) and distribute

to students. Have students work in pairs, encouraging them to discuss strategies they

might use to solve the problem. You may want to walk around and listen in on some

of their discussions. After a few minutes, display the problem on the board (or on the

overhead if you made a transparency) and use the following questions to guide a

whole-class discussion on how to solve the problem:

What do you see? (4 chevron stamps, one 5¢ stamp, and a receipt showing a total cost

of 13¢)

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