This lesson allows students to practice using the formula for the area of parallelograms, and to choose the measurements to use as a base and its corresponding height.

The parallelograms are shown both on and off a grid. As students work to find the areas, they begin to see that some measurements are more helpful than others. For example, if a parallelogram on a grid has a vertical or horizontal side, and one of those sides is used as a base, then both the base and the height can be relatively easily determined.. As students think about which measurements to use, they practice looking for and making use of structure (MP7).

Students also see that parallelograms with the same base and the same height have the same area because the products of those two numbers are equal, even if the parallelograms look very different.