Lesson 4

Exploring with Base-Ten Pieces

Est. Class Sessions: 2

Daily Practice and Problems

Teacher Notes
X

Use DPP item M to practice the addition facts in Group E.

Discuss students' strategies including reasoning from known facts. Using ten and using doubles are also efficient strategies.

  1. 13
  2. 12
  3. 13
  4. 13
  5. 12
  6. 12
  7. 12
  8. 11

Possible response:

2 + 10 = 12. 3 is one more than 2 and 9 is one less than 10, so 2 + 10 is equal to 3 + 9.

M. What Is the Sum

  1. 9 + 4 =
  2. 7 + 5 =
  3. 8 + 5 =
  4. 10 + 3 =
  5. = 2 + 10
  6. = 3 + 9
  7. = 4 + 8
  8. 10 + 1 =
  1. Explain how knowing the answer to 2 + 10 can help you solve 3 + 9.