Lesson 1

Addition Strategies

Est. Class Sessions: 2

Daily Practice and Problems

Teacher Notes
X

TIMS Task

Use this DPP to review the subtraction facts in Group 1.

Students may use manipulatives or pictures to show that 15 − 9 = 6. They may also suggest asking Mike to add 9 + 7 = 16 to show that 7 is not correct. Then they may use a ten to arrive at the correct answer: 15 − 10 is 5, so subtracting 9 instead of 10 will be one more, or 6.

D. Terry and Mike Smart

Terry is helping Mike with his homework. Mike says 15 − 9 = 7. Terry is trying to show Mike he is wrong. How do you think Mike should correct his mistake?