This problem with multiple solutions offers an opportunity for students to practice simple addition and subtraction, work with number sentences (equations), and develop systematic work habits. Given cards containing the addition, subtraction and equal signs along with the digits 2, 4, 6, and 8. solvers are challenged to find as many ways as possible to arrange some or all seven cards to create true statements. The Teachers' Notes page offers suggestions for implementation, discussion questions, ideas for extension and support, printable cards (pdf) and a link to an interactive Flash applet.

This short video and interactive assessment activity is designed to teach second graders about adding and subtracting (numbers up to 20) - word problems.

Breakout (Escape) Room game for helping students use 4C 21st Century Skills (Critical Thinking, Creativity, Collaboration and Communication) as well as fluently subtracting with nubers 0-20. Students will use a clue to help them figure out the letter combination to unlock the LOCK. 

This Nim-like interactive Flash game provides an opportunity to practice basic addition and subtraction while developing strategic thinking through generalization and by applying knowledge of factors and multiples. It can be played against the computer or a friend. Players take turns adding a whole number from 1 to 4 to a running total. The player who hits the target of 23 wins. Computer settings allow changing the target number, the range of numbers to add, who goes first, and whether the player reading the target wins or loses. The Teachers' Notes page offers suggestions for implementation, discussion questions, ideas for support, and links to related games.

In this problem students practice addition and subtraction (and possibly multiplication) while developing systematic work strategies. Given two types of ladybirds, each with either 4 or 7 spots, learners explore ways of combining them to achieve different total numbers of spots. The Teachers' Notes page offers rationale, suggestions for implementation, discussion questions, ideas for extension and support, and links to related games.

In this problem students practice counting by twos as they explore the natural phenomenon that legs on creatures always come in pairs, laying the foundation for doubling and halving. A set of cards can be downloaded (pdf) and matched. The Teachers' Notes page offers suggestions for implementation, discussion questions, ideas for extension and support, an expanded set of cards (pdf), and links to related activities (Noah and Number Tracks, both cataloged separately).

This article is devoted to the mathematical topic of negative numbers and provides a series of primary resources designed to familiarize children with the notion of counting on either side of a central point. The article presents that the activities listed should be played sequentially to build precursory ideas in understanding negative numbers. All the games discussed in the article are linked on the page and have been cataloged separately: Incy Wincy Spider, Tug of War, Swimming Pool, Tug Harder, First Connect Three and lastly Sea Level.

This game for two players provides students with practice in whole number addition and subtraction while developing strategic thinking. It is played on paper on a 0-20 number line. Player 1 crosses off two numbers and circles either their sum or difference. In each successive turn players cross off the last circled number and one of their choice, and then circle the sum or difference. The player who makes the last possible move wins. The game also may be played co-operatively. The Teachers' Notes page offers suggestions for introducing the game, discussion questions, and extension ideas.

This is a paper and pencil version of an old game. It is fun for young children and anyone can enjoy the game of chance mixed with the fun of finding a strategy. There is even more opportunity for conversation about odds and probability.