Khan Academy Static

Subtraction_with_regrouping_within_1000

Learn how to subtract numbers like 363 - 259. These subtraction problems are a harder than the ones we've done before because they require regrouping (also called borrowing).

Strategies_for_adding_and_subtracting_within_100

Learn strategies for adding and subtracting 2-digit numbers.

Word_problems_within_100

Learn how to solve addition and subtraction word problems. Numbers used 100 or less.

Subtraction_within_100

Learn to subtract two-digit numbers like 47 and 39.

Addition_with_regrouping_within_1000

Learn how to add numbers like 259 + 363. These addition problems are a harder than the ones we've done before because they require regrouping (also called carrying).

Addition_and_subtraction_within_20

Add and subtract numbers 20 or less. Find the missing number in addition and subtraction equations.

Basic_addition_and_subtraction

Adding and subtracting is the basis of all mathematics. This tutorial introduces you to one-digit addition and subtraction.

Addition_within_100

Learn to add two-digit numbers like 37 and 49.