Khan Academy

Regrouping to add 1-digit number (K-A)

Adding 53+17 by making a group of 10 (K-A)

Adding by making a group of 10 (K-A)

Addition and subtraction with number lines (K-A)

Strategies for adding 2-digit numbers (K-A)

Adding 2-digit numbers without regrouping 2 (K-A)

Adding with regrouping (K-A)

Subtracting 2-digit numbers without regrouping 1 (K-A)

Subtracting with regrouping (borrowing) (K-A)

Adding and subtracting on number line word problems (K-A)

Addition word problem: horses (K-A)

Subtraction word problem: crayons (K-A)

Subtraction word problem: snow (K-A)

Subtraction word problem: tennis balls (K-A)

Addition word problem: spots (K-A)

Addition word problem: starfish (K-A)

Subtraction word problem: basketball (K-A)

Counting by 10s (K-A)

Skip-counting by 100s (K-A)

Skip-counting by 5s (K-A)

Missing numbers in addition and subtraction (K-A)

Estimating adding and subtracting 3-digit numbers (K-A)

Adding 10 or 100 (K-A)

Adding 1s, 10s, and 100s-video (K-A)

Adding 3-digit numbers (no regrouping) (K-A)