How can you use just one weighing to find out which box contains
the lighter ten coins out of the ten boxes?
Can you place the numbers from 1 to 10 in the grid?
If there is a ring of six chairs and thirty children must either
sit on a chair or stand behind one, how many children will be
behind each chair?
You can make a calculator count for you by any number you choose.
You can count by ones to reach 24. You can count by twos to reach
24. What else can you count by to reach 24?
Pat counts her sweets in different groups and both times she has
some left over. How many sweets could she have had?
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?
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?
Can you see how these factor-multiple chains work? Find the chain which contains the smallest possible numbers. How about the largest possible numbers?
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 find the chosen number from the grid using the clues?
This activity focuses on doubling multiples of five.
Use this grid to shade the numbers in the way described. Which
numbers do you have left? Do you know what they are called?
Investigate which numbers make these lights come on. What is the smallest number you can find that lights up all the lights?
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.
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.
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 complete this jigsaw of the multiplication square?
What is the lowest number which always leaves a remainder of 1 when
divided by each of the numbers from 2 to 10?
Find the squares that Froggie skips onto to get to the pumpkin patch. She starts on 3 and finishes on 30, but she lands only on a square that has a number 3 more than the square she skips from.
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?
Help share out the biscuits the children have made.
Mr Gilderdale is playing a game with his class. What rule might he have chosen? How would you test your idea?
Can you order the digits from 1-3 to make a number which is divisible by 3 so when the last digit is removed it becomes a 2-figure number divisible by 2, and so on?
Use cubes to continue making the numbers from 7 to 20. Are they sticks, rectangles or squares?
Use the interactivities to complete these Venn diagrams.
These red, yellow and blue spinners were each spun 45 times in
total. Can you work out which numbers are on each spinner?
This article for teachers describes how number arrays can be a
useful reprentation for many number concepts.
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?
If you have only four weights, where could you place them in order
to balance this equaliser?
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?
Which is quicker, counting up to 30 in ones or counting up to 300 in tens? Why?
Look at the squares in this problem. What does the next square look
like? I draw a square with 81 little squares inside it. How long
and how wide is my square?
Follow the clues to find the mystery number.
On a farm there were some hens and sheep. Altogether there were 8 heads and 22 feet. How many hens were there?
Can you work out what a ziffle is on the planet Zargon?
There are ten children in Becky's group. Can you find a set of
numbers for each of them? Are there any other sets?
56 406 is the product of two consecutive numbers. What are these
Work out Tom's number from the answers he gives his friend. He will
only answer 'yes' or 'no'.
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?
Can you help the children in Mrs Trimmer's class make different
shapes out of a loop of string?
Number problems at primary level to work on with others.
Use the interactivity to sort these numbers into sets. Can you give
each set a name?
Does a graph of the triangular numbers cross a graph of the six
times table? If so, where? Will a graph of the square numbers cross
the times table too?
An investigation that gives you the opportunity to make and justify
Number problems at primary level that may require determination.
How many trains can you make which are the same length as Matt's, using rods that are identical?
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?
Are these statements always true, sometimes true or never true?
Got It game for an adult and child. How can you play so that you know you will always win?
Katie and Will have some balloons. Will's balloon burst at exactly
the same size as Katie's at the beginning of a puff. How many puffs
had Will done before his balloon burst?