Calculation Nation

NCTM's Illuminations site includes Calculation Nation.  Students may play the games to challenge themselves, playing against the computer, or they may challenge another online player. 

The games practice multiplication facts, factors, prime numbers, area, perimeter and other upper elementary through middle school concepts and skills.  All games add an element of strategy so that students are prompted to try several possible moves before selecting the best move that garners the most points.  Students won't realize they're really doing math as they PLAY these games and they'll keep playing to try to improve their scores and beat the computer or their online opponent.

Add this free resource to your online sites and encourage students to practice regularly.  They may enjoy playing each other, parents, older siblings or students from other schools.

Factor Blaster

Students must think about the factors of each number as they play this game.   Students quickly learn the value of selecting prime numbers as a strategy.   The beauty of the game design is that students will review the factors of many numbers and mentally add the sum of these factors together in search of the "best move." 

Basically, start with the numbers 1-25.  The first student may choose any number and gets that many points.  The second student identifies and keeps any factors of that number that are still on the board.  Play then switches with the second student picking any number, and the first student identifying and taking any factors of the chosen number that still remain on the playing board.

This means that students have to think carefully about the number they choose, mentally identifying and tallying any factors left on the board.  So, the game provides lots of practice in identifying all of the factors of these numbers.  Students quickly strategize and learn that prime numbers make great early picks that provide no points for their opponent.


Note:  Factor Blaster is very close to Factor Game, but Factor Blaster allows students to take numbers, even if there are no factors left on the board.  Students not only learn factors; they also master the prime numbers which is a great skill for prime factorization.

Classroom Management Suggestions:

• Introduce the game by playing against the class or by dividing the class into two teams and playing on the overhead or using large numbers on the board.
• Use cheap cookie sheets and magnetic number cards to create easy versions of the game for partner play.  All of the numbers fit on the cookie sheet and the cookie sheets nest within each other for easy storage.  Dollar stores are a great place to find cheap cookie sheets for this purpose. 

 Differentiation:

• Use different ranges of numbers to challenge students or remove a couple of numbers to shake up the usual game
• Allow basic skills students to use lists of factors as they begin to play the game OR begin with the numbers 1-12 and increase the range as students master the factors of these numbers 

Check out Factor Blaster on Mathwire for additional discussion of the rules, classroom management suggestions and to download number cards and directions for the game.