These activities are part of our Primary collections, which are problems grouped by topic.

### One Big Triangle

##### Age 5 to 7Challenge Level

Make one big triangle so the numbers that touch on the small triangles add to 10.

### Subtraction Slip

##### Age 5 to 7Challenge Level

Can you spot the mistake in this video? How would you work out the answer to this calculation?

### Pairs of Numbers

##### Age 5 to 7Challenge Level

If you have ten counters numbered 1 to 10, how many can you put into pairs that add to 10? Which ones do you have to leave out? Why?

### Butterfly Flowers

##### Age 5 to 7Challenge Level

Can you find 2 butterflies to go on each flower so that the numbers on each pair of butterflies adds to the same number as the one on the flower?

### Equivalent Pairs

##### Age 5 to 7Challenge Level

Can you match pairs of cards which show the same amount?

### Number Lines

##### Age 5 to 7Challenge Level

A resource to try once children are familiar with number lines, and they have begun to use them for addition. It could be a good way to talk about subtraction. Leah and Tom each have a number line. Can you work out where their counters will land?

### Two Spinners

##### Age 5 to 7Challenge Level

What two-digit numbers can you make with these two dice? What can't you make?

### The Add and Take-away Path

##### Age 5 to 7Challenge Level

Two children made up a game as they walked along the garden paths. Can you find out their scores? Can you find some paths of your own?

### What Could It Be?

##### Age 5 to 7Challenge Level

In this calculation, the box represents a missing digit. What could the digit be? What would the solution be in each case?

### Cuisenaire Counting

##### Age 5 to 7Challenge Level

Here are some rods that are different colours. How could I make a yellow rod using white and red rods?

### Two Dice

##### Age 5 to 7Challenge Level

Find all the numbers that can be made by adding the dots on two dice.

### Unit Differences

##### Age 5 to 7Challenge Level

This challenge is about finding the difference between numbers which have the same tens digit.

### What's in a Name?

##### Age 5 to 7Challenge Level

What do you notice about these squares of numbers? What is the same? What is different?

### Sort Them Out (1)

##### Age 5 to 7Challenge Level

Can you each work out the number on your card? What do you notice? How could you sort the cards?

### Number Balance

##### Age 5 to 7Challenge Level

Can you hang weights in the right place to make the the number balance balanced?

### What Was in the Box?

##### Age 5 to 7Challenge Level

This big box adds something to any number that goes into it. If you know the numbers that come out, what addition might be going on in the box?

### How Many?

##### Age 5 to 7Challenge Level

This project challenges you to work out the number of cubes hidden under a cloth. What questions would you like to ask?

### Arranging Additions and Sorting Subtractions

##### Age 5 to 7Challenge Level

Order these four calculations from easiest to hardest. How did you decide?

### Domino Sorting

##### Age 5 to 7Challenge Level

Try grouping the dominoes in the ways described. Are there any left over each time? Can you explain why?

### Doing and Undoing

##### Age 5 to 11Challenge Level

An investigation looking at doing and undoing mathematical operations focusing on doubling, halving, adding and subtracting.

### Sitting Round the Party Tables

##### Age 5 to 11Challenge Level

Sweets are given out to party-goers in a particular way. Investigate the total number of sweets received by people sitting in different positions.

### How Do You See It?

##### Age 5 to 11Challenge Level

Here are some short problems for you to try. Talk to your friends about how you work them out.

### Half Time

##### Age 5 to 11Challenge Level

What could the half time scores have been in these Olympic hockey matches?

### Strike it Out

##### Age 5 to 11Challenge Level

Use your addition and subtraction skills, combined with some strategic thinking, to beat your partner at this game.

##### Age 5 to 11Challenge Level

Who said that adding couldn't be fun?

### Cuisenaire Environment

##### Age 5 to 16Challenge Level

An environment which simulates working with Cuisenaire rods.

##### Age 5 to 7Challenge Level

There are three baskets, a brown one, a red one and a pink one, holding a total of 10 eggs. How many eggs are in each basket?

### Secret Number

##### Age 5 to 7Challenge Level

Annie and Ben are playing a game with a calculator. What was Annie's secret number?

### Birthday Cakes

##### Age 5 to 7Challenge Level

Jack's mum bought some candles to use on his birthday cakes and when his sister was born, she used them on her cakes too. Can you use the information to find out when Kate was born?

### Find the Difference

##### Age 5 to 7Challenge Level

Place the numbers 1 to 6 in the circles so that each number is the difference between the two numbers just below it.

### Noah

##### Age 5 to 7Challenge Level

Noah saw 12 legs walk by into the Ark. How many creatures did he see?

##### Age 5 to 7Challenge Level

On a farm there were some hens and sheep. Altogether there were 8 heads and 22 feet. How many hens were there?

### Jumping Squares

##### Age 5 to 7Challenge Level

In this problem it is not the squares that jump, you do the jumping! The idea is to go round the track in as few jumps as possible.

##### Age 5 to 7Challenge Level

In Sam and Jill's garden there are two sorts of ladybirds with 7 spots or 4 spots. What numbers of total spots can you make?

### The Brown Family

##### Age 5 to 7Challenge Level

Use the information about Sally and her brother to find out how many children there are in the Brown family.

### The Tall Tower

##### Age 5 to 7Challenge Level

As you come down the ladders of the Tall Tower you collect useful spells. Which way should you go to collect the most spells?

### 2,4,6,8

##### Age 5 to 7Challenge Level

Using the cards 2, 4, 6, 8, +, - and =, what number statements can you make?

### Number Round Up

##### Age 5 to 7Challenge Level

Arrange the numbers 1 to 6 in each set of circles below. The sum of each side of the triangle should equal the number in its centre.