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?
Try to stop your opponent from being able to split the piles of counters into unequal numbers. Can you find a strategy?
An odd version of tic tac toe
Investigate which numbers make these lights come on. What is the smallest number you can find that lights up all the lights?
Mr Gilderdale is playing a game with his class. What rule might he have chosen? How would you test your idea?
Can you complete this jigsaw of the multiplication square?
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?
Can you hang weights in the right place to make the equaliser
An environment which simulates working with Cuisenaire rods.
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?
Investigate the smallest number of moves it takes to turn these
mats upside-down if you can only turn exactly three at a time.
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?
If you have only four weights, where could you place them in order
to balance this equaliser?
Here is a chance to play a version of the classic Countdown Game.
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?
Use the number weights to find different ways of balancing the equaliser.
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!
Choose four of the numbers from 1 to 9 to put in the squares so
that the differences between joined squares are odd.
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?
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....?
Match the halves.
Play this well-known game against the computer where each player is
equally likely to choose scissors, paper or rock. Why not try the
Can you work out how to balance this equaliser? You can put more
than one weight on a hook.
This problem is based on a code using two different prime numbers
less than 10. You'll need to multiply them together and shift the
alphabet forwards by the result. Can you decipher the code?
Can you put the 25 coloured tiles into the 5 x 5 square so that no
column, no row and no diagonal line have tiles of the same colour
Arrange the four number cards on the grid, according to the rules,
to make a diagonal, vertical or horizontal line.
Make one big triangle so the numbers that touch on the small triangles add to 10. You could use the interactivity to help you.
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?
Ben and his mum are planting garlic. Use the interactivity to help
you find out how many cloves of garlic they might have had.
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.
Use the interactivity to find out how many quarter turns the man
must rotate through to look like each of the pictures.
This article gives you a few ideas for understanding the Got It! game and how you might find a winning strategy.
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?
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?
Use the information about Sally and her brother to find out how many children there are in the Brown family.
Imagine a wheel with different markings painted on it at regular
intervals. Can you predict the colour of the 18th mark? The 100th
A generic circular pegboard resource.
Exchange the positions of the two sets of counters in the least possible number of moves
Yasmin and Zach have some bears to share. Which numbers of bears
can they share so that there are none left over?
A variant on the game Alquerque
Move just three of the circles so that the triangle faces in the
Can you see why 2 by 2 could be 5? Can you predict what 2 by 10
What do the numbers shaded in blue on this hundred square have in common? What do you notice about the pink numbers? How about the shaded numbers in the other squares?
Use the interactivity to sort these numbers into sets. Can you give
each set a name?
Can you put the numbers from 1 to 15 on the circles so that no
consecutive numbers lie anywhere along a continuous straight line?
Choose a symbol to put into the number sentence.
Can you put the numbers 1 to 8 into the circles so that the four
calculations are correct?
Use the interactivities to complete these Venn diagrams.
Place the numbers 1 to 10 in the circles so that each number is the
difference between the two numbers just below it.