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?

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.

Got It game for an adult and child. How can you play so that you know you will always win?

Mr Gilderdale is playing a game with his class. What rule might he have chosen? How would you test your idea?

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 is quicker, counting up to 30 in ones or counting up to 300 in tens? Why?

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.

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?

Can you work out how to balance this equaliser? You can put more than one weight on a hook.

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?

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.

Does this 'trick' for calculating multiples of 11 always work? Why or why not?

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?

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?

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

Investigate the smallest number of moves it takes to turn these mats upside-down if you can only turn exactly three at a time.

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 which numbers make these lights come on. What is the smallest number you can find that lights up all the lights?

Your vessel, the Starship Diophantus, has become damaged in deep space. Can you use your knowledge of times tables and some lightning reflexes to survive?

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

Ben and his mum are planting garlic. Use the interactivity to help you find out how many cloves of garlic they might have had.

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

What is the lowest number which always leaves a remainder of 1 when divided by each of the numbers from 2 to 10?

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

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

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?

Find the words hidden inside each of the circles by counting around a certain number of spaces to find each letter in turn.

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?

Pat counts her sweets in different groups and both times she has some left over. How many sweets could she have had?

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?

Yasmin and Zach have some bears to share. Which numbers of bears can they share so that there are none left over?

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

How many trains can you make which are the same length as Matt's, using rods that are identical?

Use this grid to shade the numbers in the way described. Which numbers do you have left? Do you know what they are called?

If you have only four weights, where could you place them in order to balance this equaliser?

Can you sort numbers into sets? Can you give each set a name?

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

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

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

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?

Which pairs of cogs let the coloured tooth touch every tooth on the other cog? Which pairs do not let this happen? Why?

Investigate the sum of the numbers on the top and bottom faces of a line of three dice. What do you notice?