Lee was writing all the counting numbers from 1 to 20. She stopped for a rest after writing seventeen digits. What was the last number she wrote?

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

What do you see as you watch this video? Can you create a similar video for the number 12?

Use these head, body and leg pieces to make Robot Monsters which are different heights.

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

Buzzy Bee was building a honeycomb. She decorated the honeycomb with a pattern using numbers. Can you discover Buzzy's pattern and fill in the empty cells for her?

This is a game in which your counters move in a spiral round the snail's shell. It is about understanding tens and units.

Can you use the numbers on the dice to reach your end of the number line before your partner beats you?

How would you create the largest possible two-digit even number from the digit I've given you and one of your choice?

Use five steps to count forwards or backwards in 1s or 10s to get to 50. What strategies did you use?

There are three versions of this challenge. The idea is to change the colour of all the spots on the grid. Can you do it in fewer throws of the dice?

Andrew decorated 20 biscuits to take to a party. He lined them up and put icing on every second biscuit and different decorations on other biscuits. How many biscuits weren't decorated?

You have a set of the digits from 0 – 9. Can you arrange these in the five boxes to make two-digit numbers as close to the targets as possible?

How could you estimate the number of pencils/pens in these pictures?

Here's a very elementary code that requires young children to read a table, and look for similarities and differences.

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

Can you work out the domino pieces which would go in the middle in each case to complete the pattern of these eight sets of 3 dominoes?

Kimie and Sebastian were making sticks from interlocking cubes and lining them up. Can they make their lines the same length? Can they make any other lines?

If you put three beads onto a tens/ones abacus you could make the numbers 3, 30, 12 or 21. What numbers can be made with six beads?

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

An activity centred around observations of dots and how we visualise number arrangement patterns.

Try out this number trick. What happens with different starting numbers? What do you notice?

Exploring the structure of a number square: how quickly can you put the number tiles in the right place on the grid?

In this investigation we are going to count the number of 1s, 2s, 3s etc in numbers. Can you predict what will happen?

Have a look at these photos of different fruit. How many do you see? How did you count?

Dotty Six is a simple dice game that you can adapt in many ways.