Start by putting one million (1 000 000) into the display of your
calculator. Can you reduce this to 7 using just the 7 key and add,
subtract, multiply, divide and equals as many times as you like?
Investigate which numbers make these lights come on. What is the smallest number you can find that lights up all the lights?
Can you hang weights in the right place to make the equaliser
Choose four of the numbers from 1 to 9 to put in the squares so that the differences between joined squares are odd.
How have the numbers been placed in this Carroll diagram? Which
labels would you put on each row and column?
Use the interactivities to fill in these Carroll diagrams. How do you know where to place the numbers?
Use the interactivities to complete these Venn diagrams.
What happens when you try and fit the triomino pieces into these
Can you find all the different ways of lining up these Cuisenaire
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....?
Can you cover the camel with these pieces?
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?
Can you make a train the same length as Laura's but using three differently coloured rods? Is there only one way of doing it?
Try to stop your opponent from being able to split the piles of counters into unequal numbers. Can you find a strategy?
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?
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?
In your bank, you have three types of coins. The number of spots shows how much they are worth. Can you choose coins to exchange with the groups given to make the same total?
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!
Make one big triangle so the numbers that touch on the small triangles add to 10. You could use the interactivity to help you.
A game to be played against the computer, or in groups. Pick a 7-digit number. A random digit is generated. What must you subract to remove the digit from your number? the first to zero wins.
An odd version of tic tac toe
Place the numbers 1 to 6 in the circles so that each number is the
difference between the two numbers just below it.
Use the information about Sally and her brother to find out how many children there are in the Brown family.
Can you complete this jigsaw of the multiplication square?
Hover your mouse over the counters to see which ones will be
removed. Click to remover them. The winner is the last one to
remove a counter. How you can make sure you win?
Investigate the smallest number of moves it takes to turn these
mats upside-down if you can only turn exactly three at a time.
Can you see why 2 by 2 could be 5? Can you predict what 2 by 10
This 100 square jigsaw is written in code. It starts with 1 and ends with 100. Can you build it up?
Use the number weights to find different ways of balancing the equaliser.
Mr Gilderdale is playing a game with his class. What rule might he have chosen? How would you test your idea?
Can you put the numbers from 1 to 15 on the circles so that no
consecutive numbers lie anywhere along a continuous straight line?
Can you make a cycle of pairs that add to make a square number
using all the numbers in the box below, once and once only?
Choose a symbol to put into the number sentence.
Use the clues to colour each square.
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
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?
The computer has made a rectangle and will tell you the number of spots it uses in total. Can you find out where the rectangle is?
Imagine a wheel with different markings painted on it at regular
intervals. Can you predict the colour of the 18th mark? The 100th
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?
Three beads are threaded on a circular wire and are coloured either red or blue. Can you find all four different combinations?
How many different rhythms can you make by putting two drums on the
An interactive game to be played on your own or with friends.
Imagine you are having a party. Each person takes it in turns to
stand behind the chair where they will get the most chocolate.
An interactive activity for one to experiment with a tricky tessellation
Train game for an adult and child. Who will be the first to make the train?
A tetromino is made up of four squares joined edge to edge. Can
this tetromino, together with 15 copies of itself, be used to cover
an eight by eight chessboard?
Board Block game for two. Can you stop your partner from being able to make a shape on the board?
Incey Wincey Spider game for an adult and child. Will Incey get to the top of the drainpipe?
Move just three of the circles so that the triangle faces in the
Stop the Clock game for an adult and child. How can you make sure you always win this game?