Unit 5, Lesson 15# Use math drawings to represent subtraction with up to two decompositions, relate drawings to the algorithm, and use addition to explain why the subtraction method works

EngageNY 60 min(s)

In this lesson, students continue to build their conceptual understanding of subtracting numbers within 1,000. They continue to move from concrete to pictorial representation, as they use chip models to represent decompositions while simultaneously recording these changes in vertical form. This helps them to relate the pictorial representation to the standing vertical algorithm. Students check their work with addition.