The computer starts with all the lights off, but then clicks 3, 4 or 5 times at random, leaving some lights on. Can you switch them off again?

Advent Calendar 2010 - a mathematical game for every day during the run-up to Christmas.

A game for 2 people. Take turns to move the counters 1, 2 or 3 spaces. The player to remove the last counter off the board wins.

A game for 2 people. Take turns joining two dots, until your opponent is unable to move.

Slide the pieces to move Khun Phaen past all the guards into the position on the right from which he can escape to freedom.

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

This second Sudoku article discusses "Corresponding Sudokus" which are pairs of Sudokus with terms that can be matched using a substitution rule.

Given the products of diagonally opposite cells - can you complete this Sudoku?

A Sudoku that uses transformations as supporting clues.

Two sudokus in one. Challenge yourself to make the necessary connections.

Here is a solitaire type environment for you to experiment with. Which targets can you reach?

Four numbers on an intersection that need to be placed in the surrounding cells. That is all you need to know to solve this sudoku.

Two sudokus in one. Challenge yourself to make the necessary connections.

A game for 2 players. Can be played online. One player has 1 red counter, the other has 4 blue. The red counter needs to reach the other side, and the blue needs to trap the red.

A Sudoku with clues given as sums of entries.

This sudoku requires you to have "double vision" - two Sudoku's for the price of one

This pair of linked Sudokus matches letters with numbers and hides a seasonal greeting. Can you find it?

Nim-7 game for an adult and child. Who will be the one to take the last counter?

Square It game for an adult and child. Can you come up with a way of always winning this game?

Unmultiply is a game of quick estimation. You need to find two numbers that multiply together to something close to the given target - fast! 10 levels with a high scores table.

A game for 1 person. Can you work out how the dice must be rolled from the start position to the finish? Play on line.

Players take it in turns to choose a dot on the grid. The winner is the first to have four dots that can be joined to form a square.

A game for 2 players. Given a board of dots in a grid pattern, players take turns drawing a line by connecting 2 adjacent dots. Your goal is to complete more squares than your opponent.

The aim of the game is to slide the green square from the top right hand corner to the bottom left hand corner in the least number of moves.

A game for 1 or 2 people. Use the interactive version, or play with friends. Try to round up as many counters as possible.

A game that tests your understanding of remainders.

A game for 2 players that can be played online. Players take it in turns to select a word from the 9 words given. The aim is to select all the occurrences of the same letter.

This article for teachers describes several games, found on the site, all of which have a related structure that can be used to develop the skills of strategic planning.

Exchange the positions of the two sets of counters in the least possible number of moves

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

An extension of noughts and crosses in which the grid is enlarged and the length of the winning line can to altered to 3, 4 or 5.

Collect as many diamonds as you can by drawing three straight lines.

A game for 2 players. Take turns to place a counter so that it occupies one of the lowest possible positions in the grid. The first player to complete a line of 4 wins.

Can you spot the similarities between this game and other games you know? The aim is to choose 3 numbers that total 15.

An ordinary set of dominoes can be laid out as a 7 by 4 magic rectangle in which all the spots in all the columns add to 24, while those in the rows add to 42. Try it! Now try the magic square...

Here is a version of the game 'Happy Families' for you to make and play.

A game for 1 person to play on screen. Practise your number bonds whilst improving your memory

Can you make the birds from the egg tangram?

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?

A shunting puzzle for 1 person. Swop the positions of the counters at the top and bottom of the board.

A game for 2 players. Using 2 dice, some counters and a games board, can you form a line of counters from one side of the board to the other?