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?
An odd version of tic tac toe
Use the interactivities to fill in these Carroll diagrams. How do you know where to place the numbers?
This article gives you a few ideas for understanding the Got It! game and how you might find a winning strategy.
Place the numbers from 1 to 9 in the squares below so that the difference between joined squares is odd. How many different ways can you do this?
Can you complete this jigsaw of the multiplication square?
Ben and his mum are planting garlic. Use the interactivity to help
you find out how many cloves of garlic they might have had.
How have the numbers been placed in this Carroll diagram? Which
labels would you put on each row and column?
If there are 3 squares in the ring, can you place three different numbers in them so that their differences are odd? Try with different numbers of squares around the ring. What do you notice?
Investigate the smallest number of moves it takes to turn these
mats upside-down if you can only turn exactly three at a time.
You'll need two dice to play this game against a partner. Will Incey Wincey make it to the top of the drain pipe or the bottom of the drain pipe first?
Try to stop your opponent from being able to split the piles of counters into unequal numbers. Can you find a strategy?
Mr Gilderdale is playing a game with his class. What rule might he have chosen? How would you test your idea?
Here is a chance to play a version of the classic Countdown Game.
An interactive activity for one to experiment with a tricky tessellation
Match the halves.
Is it possible to place 2 counters on the 3 by 3 grid so that there
is an even number of counters in every row and every column? How
about if you have 3 counters or 4 counters or....?
An interactive game for 1 person. You are given a rectangle with 50 squares on it. Roll the dice to get a percentage between 2 and 100. How many squares is this? Keep going until you get 100. . . .
A game for 2 people that can be played on line or with pens and paper. Combine your knowledege of coordinates with your skills of strategic thinking.
Using angular.js to bind inputs to outputs
There are three versions of this challenge. The idea is to change the colour of all the spots on the grid. Can you do it in fewer throws of the dice?
Can you work out how to balance this equaliser? You can put more
than one weight on a hook.
Can you see why 2 by 2 could be 5? Can you predict what 2 by 10
Play this well-known game against the computer where each player is
equally likely to choose scissors, paper or rock. Why not try the
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.
Can you hang weights in the right place to make the equaliser
A game for 2 people that everybody knows. You can play with a
friend or online. If you play correctly you never lose!
Take it in turns to place a domino on the grid. One to be placed horizontally and the other vertically. Can you make it impossible for your opponent to play?
You have 4 red and 5 blue counters. How many ways can they be
placed on a 3 by 3 grid so that all the rows columns and diagonals
have an even number of red counters?
Starting with the number 180, take away 9 again and again, joining up the dots as you go. Watch out - don't join all the dots!
Move just three of the circles so that the triangle faces in the
A generic circular pegboard resource.
Use the interactivity to find out how many quarter turns the man
must rotate through to look like each of the pictures.
What are the coordinates of the coloured dots that mark out the
tangram? Try changing the position of the origin. What happens to
the coordinates now?
Can you complete this jigsaw of the 100 square?
A card pairing game involving knowledge of simple ratio.
Arrange the four number cards on the grid, according to the rules,
to make a diagonal, vertical or horizontal line.
Yasmin and Zach have some bears to share. Which numbers of bears
can they share so that there are none left over?
Choose four of the numbers from 1 to 9 to put in the squares so that the differences between joined squares are odd.
Ahmed has some wooden planks to use for three sides of a rabbit run
against the shed. What quadrilaterals would he be able to make with
the planks of different lengths?
Choose 13 spots on the grid. Can you work out the scoring system? What is the maximum possible score?
Use the interactivities to complete these Venn diagrams.
Twenty four games for the run-up to Christmas.
If you have only four weights, where could you place them in order
to balance this equaliser?
Find out what a "fault-free" rectangle is and try to make some of
A train building game for 2 players.
NRICH December 2006 advent calendar - a new tangram for each day in
the run-up to Christmas.
This is a game for two players. Can you find out how to be the first to get to 12 o'clock?
Use the number weights to find different ways of balancing the equaliser.
Investigate which numbers make these lights come on. What is the smallest number you can find that lights up all the lights?