Roll two red dice and a green dice. Add the two numbers on the red dice and take away the number on the green. What are all the different possible answers?

Can you work out how to win this game of Nim? Does it matter if you go first or second?

Interactive game. Set your own level of challenge, practise your table skills and beat your previous best score.

A game for two people, or play online. Given a target number, say 23, and a range of numbers to choose from, say 1-4, players take it in turns to add to the running total to hit their target.

An activity based on the game 'Pelmanism'. Set your own level of challenge and beat your own previous best score.

Have a go at this game which involves throwing two dice and adding their totals. Where should you place your counters to be more likely to win?

Use the interactivity or play this dice game yourself. How could you make it fair?

Choose the size of your pegboard and the shapes you can make. Can you work out the strategies needed to block your opponent?

Solve this Sudoku puzzle whose clues are in the form of sums of the numbers which should appear in diagonal opposite cells.

A game in which players take it in turns to choose a number. Can you block your opponent?

The idea of this game is to add or subtract the two numbers on the dice and cover the result on the grid, trying to get a line of three. Are there some numbers that are good to aim for?

In this game, you can add, subtract, multiply or divide the numbers on the dice. Which will you do so that you get to the end of the number line first?

Play this game and see if you can figure out the computer's chosen number.