Practice solving addition and subtraction problems with integers (positive and negative numbers). Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.

Khan Academy learning modules include a Community space where users can ask questions and seek help from community members. Educators should consult with their Technology administrators to determine the use of Khan Academy learning modules in their classroom. Please review materials from external sites before sharing with students.

This lesson demonstrates how to add vectors using the tail-to-tip method. It is 2 of 2 in the series titled "Adding Vectors Using the Tail-to-Tip Method." [6:52]

This is an interactive assessment and video designed to teach Adding and Subtracting (Numbers up to 20) - Word Problems to first graders.

This short video and interactive assessment activity is designed to teach fourth graders about adding and subtracting terms (numbers to 100).

Demonstrates how to add 35 to 27 using drawings of base ten cubes to represent 1s and 10s. [4:36]

Khan Academy learning modules include a Community space where users can ask questions and seek help from community members. Educators should consult with their Technology administrators to determine the use of Khan Academy learning modules in their classroom. Please review materials from external sites before sharing with students.

This short video and interactive assessment activity is designed to teach fourth graders about addition: completing the addition sentence.

The purpose of this task is to study some patterns in a small addition table. Each pattern identified persists for a larger table and if more time is available for this activity students should be encouraged to explore these patterns in larger tables.

Video tutorial demonstrates how to solve an addition word problem with numbers less than 100. [3:30]

Khan Academy learning modules include a Community space where users can ask questions and seek help from community members. Educators should consult with their Technology administrators to determine the use of Khan Academy learning modules in their classroom. Please review materials from external sites before sharing with students.

Download these worksheets to sharpen your addition skills. Sheets focus on single and multi-digit addition, addition table, column addition, and adding doubles of numbers.

Learn how to solve addition and subtraction word problems using gorillas and cookies as examples. [5:31]

Khan Academy learning modules include a Community space where users can ask questions and seek help from community members. Educators should consult with their Technology administrators to determine the use of Khan Academy learning modules in their classroom. Please review materials from external sites before sharing with students.

Given a 2-digit addition or subtraction problem, video demonstrates how to decide which number line matches up with it. [1:56]

Khan Academy learning modules include a Community space where users can ask questions and seek help from community members. Educators should consult with their Technology administrators to determine the use of Khan Academy learning modules in their classroom. Please review materials from external sites before sharing with students.

Introducing a card game that your students can play in small groups to develop their addition skills. This video focuses on addition of positive and negative numbers and briefly touches on subtraction of integers.

This course features a video review of addition up to the sum of ten for first graders.

This short video and interactive assessment activity is designed to teach second graders an overview of addition (sums to 10).

This short video and interactive assessment activity is designed to teach second graders an overview of addition.

Choose from a variety of Afterschool Adventures covering multiple subject areas. Each adventure includes a detailed plan, videos, learning games, and book suggestions.

Are your students having difficulty understanding math terminology? Try this A-Z glossary on math related terms. It's quick, easy to read, and very complete.

In this lesson, students will complete math problems with groups to reinforce the concept of completing addition using regrouping.

This lesson will assist students in visualizing and solving situations presented in word problems.