How might you use mathematics to improve your chances of guessing the number of sweets in a jar?

How many teddies are in the jar? How many teddies could you fit in your classroom?

Examine these estimates. Do they sound about right?

These Olympic quantities have been jumbled up! Can you put them back together again?

From the information you are asked to work out where the picture was taken. Is there too much information? How accurate can your answer be?

My measurements have got all jumbled up! Swap them around and see if you can find a combination where every measurement is valid.

Choose some fractions and add them together. Can you get close to 1?

Can you rank these sets of quantities in order, from smallest to largest? Can you provide convincing evidence for your rankings?

There are four equal weights on one side of the scale and an apple on the other side. What can you say that is true about the apple and the weights from the picture?

Four Go game for an adult and child. Will you be the first to have four numbers in a row on the number line?

Dicey Operations for an adult and child. Can you get close to 1000 than your partner?

Who said that adding, subtracting, multiplying and dividing couldn't be fun?

In this article for primary teachers, Ems outlines how we can encourage learners to be flexible in their approach to calculation, and why this is crucial.

Here is a chance to play a version of the classic Countdown Game.

How many ways can you find to put in operation signs (+ - x รท) to make 100?

Make an estimate of how many light fittings you can see. Was your estimate a good one? How can you decide?

Find the exact difference between the largest ball and the smallest ball on the Hepta Tree and then use this to work out the MAGIC NUMBER!

This challenge is a game for two players. Choose two of the numbers to multiply or divide, then mark your answer on the number line. Can you get four in a row?

There are nasty versions of this dice game but we'll start with the nice ones...

Can you deduce the pattern that has been used to lay out these bottle tops?

This activity challenges you to decide on the 'best' number to use in each statement. You may need to do some estimating, some calculating and some research.

Bluey-green, white and transparent squares with a few odd bits of shapes around the perimeter. But, how many squares are there of each type in the complete circle? Study the picture and make. . . .

Some Games That May Be Nice or Nasty for an adult and child. Use your knowledge of place value to beat your opponent.

Can you work out how many of each kind of pencil this student bought?

Mr. Sunshine tells the children they will have 2 hours of homework. After several calculations, Harry says he hasn't got time to do this homework. Can you see where his reasoning is wrong?

What do you notice about the date 03.06.09? Or 08.01.09? This challenge invites you to investigate some interesting dates yourself.