Four of these clues are needed to find the chosen number on this
grid and four are true but do nothing to help in finding the
number. Can you sort out the clues and find the number?
For this challenge, you'll need to play Got It! Can you explain the
strategy for winning this game with any target?
Can you find any perfect numbers? Read this article to find out more...
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.
A game that tests your understanding of remainders.
In this problem we are looking at sets of parallel sticks that
cross each other. What is the least number of crossings you can
make? And the greatest?
Which pairs of cogs let the coloured tooth touch every tooth on the
other cog? Which pairs do not let this happen? Why?
Follow the clues to find the mystery number.
Can you predict when you'll be clapping and when you'll be clicking
if you start this rhythm? How about when a friend begins a new
rhythm at the same time?
Use the interactivities to complete these Venn diagrams.
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?
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.
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?
Imagine a wheel with different markings painted on it at regular
intervals. Can you predict the colour of the 18th mark? The 100th
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.
Can you fill in this table square? The numbers 2 -12 were used to
generate it with just one number used twice.
Use the interactivity to create some steady rhythms. How could you
create a rhythm which sounds the same forwards as it does
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?
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?
In this activity, the computer chooses a times table and shifts it. Can you work out the table and the shift each time?
Can you find the chosen number from the grid using the clues?
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?
A game for 2 or more people. Starting with 100, subratct a number from 1 to 9 from the total. You score for making an odd number, a number ending in 0 or a multiple of 6.
A game in which players take it in turns to choose a number. Can you block your opponent?
Investigate the sum of the numbers on the top and bottom faces of a line of three dice. What do you notice?
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?
Investigate which numbers make these lights come on. What is the smallest number you can find that lights up all the lights?
Which is quicker, counting up to 30 in ones or counting up to 300 in tens? Why?
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.
Look at three 'next door neighbours' amongst the counting numbers. Add them together. What do you notice?
The planet of Vuvv has seven moons. Can you work out how long it is
between each super-eclipse?
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?
Yasmin and Zach have some bears to share. Which numbers of bears
can they share so that there are none left over?
How can you use just one weighing to find out which box contains
the lighter ten coins out of the ten boxes?
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.
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?
Frances and Rishi were given a bag of lollies. They shared them out evenly and had one left over. How many lollies could there have been in the bag?
This article for teachers describes how number arrays can be a
useful reprentation for many number concepts.
Arrange any number of counters from these 18 on the grid to make a
rectangle. What numbers of counters make rectangles? How many
different rectangles can you make with each number of counters?
In this maze of hexagons, you start in the centre at 0. The next
hexagon must be a multiple of 2 and the next a multiple of 5. What
are the possible paths you could take?
These red, yellow and blue spinners were each spun 45 times in
total. Can you work out which numbers are on each spinner?
When Charlie asked his grandmother how old she is, he didn't get a
straightforward reply! Can you work out how old she is?
I am thinking of three sets of numbers less than 101. Can you find
all the numbers in each set from these clues?
Each light in this interactivity turns on according to a rule. What
happens when you enter different numbers? Can you find the smallest
number that lights up all four lights?
Mr Gilderdale is playing a game with his class. What rule might he have chosen? How would you test your idea?
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.
"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
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?
Nearly all of us have made table patterns on hundred squares, that
is 10 by 10 grids. This problem looks at the patterns on
differently sized square grids.
How many trains can you make which are the same length as Matt's,
using rods that are identical?