Students will learn how to find the area of a rectangle by multiplying. Students will also learn how to find the area of composite rectangles by adding or subtracting the areas of rectangles. Conclude by challenging your students to find the area of this trapezoid:

Watch these Khan Academy videos:

- Comparing areas of plots of land
- Finding missing side when given area
- Decomposing shapes to find area: grids
- Area word problem: house size
- Transitioning from unit squares to area formula
- Measuring rectangles with different unit squares
- Area and the distributive property
- Decomposing shapes to find area: add
- Decomposing shapes to find area: subtract

Do these Khan Academy exercises:

Conclude by leading this investigation:

Lazy Toad Puzzles (counting, symmetry)

by MathPickle

3.MD.C.7: Relate area to the operations of multiplication and addition. Recognize that area is additive. That is, we can decompose shapes, find their isolated areas, then add to find the total area.