On the planet Vuv there are two sorts of creatures. The Zios have 3 legs and the Zepts have 7 legs. The great planetary explorer Nico counted 52 legs. How many Zios and how many Zepts were there?
48 is called an abundant number because it is less than the sum of
its factors (without itself). Can you find some more abundant
Can you fill in this table square? The numbers 2 -12 were used to
generate it with just one number used twice.
I throw three dice and get 5, 3 and 2. Add the scores on the three
dice. What do you get? Now multiply the scores. What do you notice?
Suppose we allow ourselves to use three numbers less than 10 and
multiply them together. How many different products can you find?
How do you know you've got them all?
The planet of Vuvv has seven moons. Can you work out how long it is
between each super-eclipse?
Ben’s class were making cutting up number tracks. First they
cut them into twos and added up the numbers on each piece. What
patterns could they see?
What is the lowest number which always leaves a remainder of 1 when
divided by each of the numbers from 2 to 10?
Can you work out the arrangement of the digits in the square so
that the given products are correct? The numbers 1 - 9 may be used
once and once only.
56 406 is the product of two consecutive numbers. What are these
Factor track is not a race but a game of skill. The idea is to go
round the track in as few moves as possible, keeping to the rules.
Can you order the digits from 1-6 to make a number which is
divisible by 6 so when the last digit is removed it becomes a
5-figure number divisible by 5, and so on?
There is a clock-face where the numbers have become all mixed up. Can you find out where all the numbers have got to from these ten statements?
How many different shaped boxes can you design for 36 sweets in one
layer? Can you arrange the sweets so that no sweets of the same
colour are next to each other in any direction?
What happens if you join every second point on this circle? How
about every third point? Try with different steps and see if you
can predict what will happen.
Work out Tom's number from the answers he gives his friend. He will
only answer 'yes' or 'no'.
How many different sets of numbers with at least four members can
you find in the numbers in this box?
There are a number of coins on a table.
One quarter of the coins show heads.
If I turn over 2 coins, then one third show heads. How many coins are there altogether?
Can you make square numbers by adding two prime numbers together?
This big box multiplies anything that goes inside it by the same number. If you know the numbers that come out, what multiplication might be going on in the box?
Have a go at balancing this equation. Can you find different ways of doing it?
Norrie sees two lights flash at the same time, then one of them
flashes every 4th second, and the other flashes every 5th second.
How many times do they flash together during a whole minute?
Can you see how these factor-multiple chains work? Find the chain
which contains the smallest possible numbers. How about the largest
An investigation that gives you the opportunity to make and justify
This article for teachers describes how number arrays can be a
useful reprentation for many number concepts.
In a square in which the houses are evenly spaced, numbers 3 and 10
are opposite each other. What is the smallest and what is the
largest possible number of houses in the square?
When Charlie asked his grandmother how old she is, he didn't get a
straightforward reply! Can you work out how old she is?
"Ip dip sky blue! Who's 'it'? It's you!" Where would you position
yourself so that you are 'it' if there are two players? Three
A game for 2 people using a pack of cards Turn over 2 cards and try
to make an odd number or a multiple of 3.
Which is quicker, counting up to 30 in ones or counting up to 300 in tens? Why?
Can you complete this calculation by filling in the missing numbers? In how many different ways can you do it?
The discs for this game are kept in a flat square box with a square
hole for each disc. Use the information to find out how many discs
of each colour there are in the box.
Is it possible to draw a 5-pointed star without taking your pencil
off the paper? Is it possible to draw a 6-pointed star in the same
way without taking your pen off?
Arrange the four number cards on the grid, according to the rules,
to make a diagonal, vertical or horizontal line.
Nine squares with side lengths 1, 4, 7, 8, 9, 10, 14, 15, and 18 cm can be fitted together to form a rectangle. What are the dimensions of the rectangle?
Can you work out some different ways to balance this equation?
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?
There are ten children in Becky's group. Can you find a set of
numbers for each of them? Are there any other sets?
Can you work out what a ziffle is on the planet Zargon?
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!
I am thinking of three sets of numbers less than 101. Can you find
all the numbers in each set from these clues?
Becky created a number plumber which multiplies by 5 and subtracts
4. What do you notice about the numbers that it produces? Can you
explain your findings?
Investigate the smallest number of moves it takes to turn these
mats upside-down if you can only turn exactly three at a time.
Investigate the sum of the numbers on the top and bottom faces of a line of three dice. What do you notice?
I am thinking of three sets of numbers less than 101. They are the
red set, the green set and the blue set. Can you find all the
numbers in the sets from these clues?
Play the divisibility game to create numbers in which the first two digits make a number divisible by 2, the first three digits make a number divisible by 3...
If you have only four weights, where could you place them in order
to balance this equaliser?
How can you use just one weighing to find out which box contains
the lighter ten coins out of the ten boxes?
These red, yellow and blue spinners were each spun 45 times in
total. Can you work out which numbers are on each spinner?
Find the words hidden inside each of the circles by counting around
a certain number of spaces to find each letter in turn.