Students view an incomplete number line and practice placing missing 2-digit numbers within 20 in the correct spot. The number line is progressively less populated, adding challenge for students as they place the missing numbers
A. Count to 2-digit numbers within 20 with or without separating a group of ten objects into a ten-frame
C. Use 10-frames and remaining dots to add and solve for 2-digit numbers within 20
D. Count 11 to 19 objects in different arrangements
E. Decompose numbers 11-20 using models involving 10-frames
F. Decompose numbers 11-20 without using models
G. Complete number sentences involving numbers 11-20