Lesson 7

Make Connections with Subtraction

Est. Class Sessions: 2

Summarizing the Lesson

Upon completion of the Use Subtraction Strategies pages, choose one problem to solve using the two paper-and-pencil methods, such as 187 – 99. Ask students to explain how they estimate the difference. Have a student model the problem with display base-ten pieces and others demonstrate the steps they took with expanded form and the compact method.

Then ask:

X
  • Did all the methods help you find the same sum?
  • Did one use less writing than another?
  • Which method do you find easiest to understand?
  • Which way or ways help you avoid making mistakes?
  • Which method do you like best?
  • Do you still have questions about a certain method?

Assign the Choose Which Way to Subtract Homework Masters after Part 3 of the lesson.

Adventure Book:
Student Activity Book:
Master: