Students will rewrite a subtraction problem as column subtraction. Then, students will use the familiar disk model to help solve the column subtraction, without regrouping
A. Solve subtraction problems using disk models
C. Solve column subtraction with scaffolding
D. Use disk models to practice exchanging into the tens
E. Solve subtraction problems with regrouping (Level 1)
F. Solve subtraction problems with regrouping (Level 2)
G. Solve subtraction problems with regrouping (Level 3)
H. Solve subtraction problems with regrouping (Level 4)
I. Solve column subtraction, making decisions about exchanging into the tens
J. Practice solving column subtraction problems independently (Part 1)
K. Practice solving column subtraction problems independently (Part 2)
L. Solve column subtraction problems with 2- and 3-digit components (Level 1)
M. Solve column subtraction problems with 2- and 3-digit components (Level 2)
N. Solve column subtraction problems with 2- and 3-digit components (Level 3)