Subtraction to 20

Subtraction with numbers up to 20

Subtraction to 20 with three or more numbers

Subtraction to 20 with one more or one less

Subtraction to 20 via inverse operation

Subtraction to 20 crossing ten

Subtraction to 20 with one more or one less, decomposing the second number

Subtraction to 20 using grouping with three numbers

Subtraction to 20 on the number line, crossing ten

On the bus: Subtraction to 20 crossing ten

Subtraction from 20 with numbers to 20

Subtracting tens and ones from numbers to 20

Subtraction to 20 with result of 0 or 1

Determining difference to 20

Subtraction to 20 using simplification

Subtraction to 20 without regrouping

Subtraction to 20 on the number line

On the bus: Subtraction to 20

Recognizing subtraction problems to 20