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Halving and Doubling

One strategy for multiplying two numbers is to double one of the numbers, take half of the other number, and then find the product of those two numbers. While some students may know this strategy, do they have a good visual in their minds as to why this strategy works? If not, consider having students make a Polypad like the one shown in the video below.

Students can start with a blank Polypad or you can share the one below. This one has numbers lines that students can change the size of as needed.

Doubling and Halves - Polypad - Mathigon
Virtual Manipulatives for Mathematics Classrooms: polygons, number and algebra tiles, fraction bars, tangram, pentominoes, and more.