EngageNY 60 min(s)

In this lesson, students apply their understanding of place value and the subtraction algorithm to subtract numbers within 200. They use place-value disk drmawings on a place-value chart. Students then model 1 hundred as 9 tens and 10 ones and practice counting to 100 both ways. Next, they model the decomposition of a hundred either in two steps (as 10 tens then decomposing 1 ten as 10 ones) or one step (as 9 tens and 10 ones) as they represent subtractions from 200.