Subtracting a three-digit number from 1,000 to practice regrouping across zeros. Use column subtraction, and use disks in a place value chart to visualize the regrouping and the subtraction
A. Subtract two 4-digit numbers with and without regrouping in two places using column subtraction and a disk model
B. Subtract multi-digit numbers with regrouping in multiple places using column subtraction
D. Subtract multi-digit numbers using the standard algorithm
E. Pretest. Finding the Area and Perimeter of a Rectangle