Lesson 4

Subtraction with Base-Ten Pieces

Est. Class Sessions: 2

Daily Practice and Problems

Teacher Notes
X

Have base-ten pieces, desk number lines, 200 Charts, and Addition Strategies Menus readily available. Students may also use open number lines and mental math strategies.

Possible responses:

  1. 84;
    45 = 40 + 5
    + 39 = 30 + 9
    70 + 14 = 84

    I used the 200 Chart to count up: move 4 spaces down, 45, 55, 65, 75, 85, then 1 space left, 84.
  2. 100; 52 + 48 = 50 + 2 + 48 and 50 + 50 = 100

N. Addition Practice

Show or tell how to solve each problem using a different strategy or tool.

  1. 45
    + 39
  2. 52 + 48 =