Can you work out how many lengths I swim each day?

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?

One quarter of these coins are heads but when I turn over two coins, one third are heads. How many coins are there?

Imagine a wheel with different markings painted on it at regular intervals. Can you predict the colour of the 18th mark? The 100th mark?

The discs for this game are kept in a flat square box with a square hole for each. Use the information to find out how many discs of each colour there are in the box.

Can you find a relationship between the number of dots on the circle and the number of steps that will ensure that all points are hit?

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?

The planet of Vuvv has seven moons. Can you work out how long it is between each super-eclipse?

Given the products of diagonally opposite cells - can you complete this Sudoku?

A collection of resources to support work on Factors and Multiples at Secondary level.

In this activity, the computer chooses a times table and shifts it. Can you work out the table and the shift each time?

These red, yellow and blue spinners were each spun 45 times in total. Can you work out which numbers are on each spinner?

56 406 is the product of two consecutive numbers. What are these two numbers?

Can you complete this jigsaw of the multiplication square?

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?

I am thinking of three sets of numbers less than 101. Can you find all the numbers in each set from these clues?

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.

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?

An environment which simulates working with Cuisenaire rods.

Ben, Jack and Emma passed counters to each other and ended with the same number of counters. How many did they start with?

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?

How can you use just one weighing to find out which box contains the lighter ten coins out of the ten boxes?

How many different rectangles can you make using this set of rods?

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.

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?

Factors and Multiples game for an adult and child. How can you make sure you win this game?

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.

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?

The items in the shopping basket add and multiply to give the same amount. What could their prices be?

Play this game and see if you can figure out the computer's chosen number.

Work out Tom's number from the answers he gives his friend. He will only answer 'yes' or 'no'.

Can you fill in this table square? The numbers 2 -12 were used to generate it with just one number used twice.

Find some examples of pairs of numbers such that their sum is a factor of their product. eg. 4 + 12 = 16 and 4 × 12 = 48 and 16 is a factor of 48.

Arrange the four number cards on the grid, according to the rules, to make a diagonal, vertical or horizontal line.

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?

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?

The clues for this Sudoku are the product of the numbers in adjacent squares.

The puzzle can be solved by finding the values of the unknown digits (all indicated by asterisks) in the squares of the $9\times9$ grid.

An investigation that gives you the opportunity to make and justify predictions.

Number problems at primary level to work on with others.

Number problems at primary level that may require resilience.

Can you find a cuboid that has a surface area of exactly 100 square units. Is there more than one? Can you find them all?

This article for teachers describes how number arrays can be a useful representation for many number concepts.

Find the highest power of 11 that will divide into 1000! exactly.

Can you find any perfect numbers? Read this article to find out more...

Can you find different ways of creating paths using these paving slabs?

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.