Investigate which numbers make these lights come on. What is the smallest number you can find that lights up all the lights?
Can you complete this jigsaw of the multiplication square?
Mr Gilderdale is playing a game with his class. What rule might he have chosen? How would you test your idea?
If you have only four weights, where could you place them in order
to balance this equaliser?
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?
Here is a chance to play a version of the classic Countdown Game.
Work out how to light up the single light. What's the rule?
An environment which simulates working with Cuisenaire rods.
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?
How have the numbers been placed in this Carroll diagram? Which
labels would you put on each row and column?
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!
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?
Arrange the four number cards on the grid, according to the rules,
to make a diagonal, vertical or horizontal line.
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?
This article gives you a few ideas for understanding the Got It! game and how you might find a winning strategy.
Have a go at this well-known challenge. Can you swap the frogs and toads in as few slides and jumps as possible?
Can you work out how to balance this equaliser? You can put more
than one weight on a hook.
Use the interactivities to fill in these Carroll diagrams. How do you know where to place the numbers?
Can you hang weights in the right place to make the equaliser
Can you put the numbers from 1 to 15 on the circles so that no
consecutive numbers lie anywhere along a continuous straight line?
Use the number weights to find different ways of balancing the equaliser.
An odd version of tic tac toe
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....?
Use the interactivity to find all the different right-angled triangles you can make by just moving one corner of the starting triangle.
Use the interactivity to find out how many quarter turns the man
must rotate through to look like each of the pictures.
Place six toy ladybirds into the box so that there are two ladybirds in every column and every row.
Match the halves.
Ben and his mum are planting garlic. Use the interactivity to help
you find out how many cloves of garlic they might have had.
What happens when you try and fit the triomino pieces into these
First Connect Three game for an adult and child. Use the dice numbers and either addition or subtraction to get three numbers in a straight line.
Can you cover the camel with these pieces?
Investigate the smallest number of moves it takes to turn these
mats upside-down if you can only turn exactly three at a time.
Try out the lottery that is played in a far-away land. What is the
chance of winning?
Can you see why 2 by 2 could be 5? Can you predict what 2 by 10
Cut four triangles from a square as shown in the picture. How many
different shapes can you make by fitting the four triangles back
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?
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?
If you hang two weights on one side of this balance, in how many different ways can you hang three weights on the other side for it to be balanced?
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?
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?
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.
Incey Wincey Spider game for an adult and child. Will Incey get to the top of the drainpipe?
Make one big triangle so the numbers that touch on the small triangles add to 10. You could use the interactivity to help you.
Imagine a wheel with different markings painted on it at regular
intervals. Can you predict the colour of the 18th mark? The 100th
Choose four of the numbers from 1 to 9 to put in the squares so that the differences between joined squares are odd.
Use the information about Sally and her brother to find out how many children there are in the Brown family.
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?
Move just three of the circles so that the triangle faces in the
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?
Here are some rods that are different colours. How could I make a dark green rod using yellow and white rods?