#### NRICH SUBTRACTION PROBLEM SOLVING KS1

Two Dice Age 5 to 7 Challenge Level: Here are some short problems for you to try. Talk to your friends about how you work them out. Can you turn over the cards which match the numbers on the dice? What model of investment and spending would you use in order to ensure the best return on the money? Find the Difference Age 5 to 7 Challenge Level:

Katie had a pack of 20 cards numbered from 1 to Can you use the information to find out which cards I have used? What’s in a Name? Getting the Balance Age 5 to 7 Challenge Level: Four bags contain a large number of 1s, 3s, 5s and 7s. These activities lend themselves to being tackled in this way. Unit Differences Age 5 to 7 Challenge Level:

Penta Post Age 7 to 11 Challenge Level: What are the secret jumps they make with their counters? What numbers of total spots can you make? Use your addition and subtraction skills, combined with some strategic thinking, to beat your partner at this game.

In this town, houses are built with one room for each person. Look at proble ‘next door neighbours’ amongst the counting numbers.

# Working Systematically at KS1 :

The idea is to go round the track in as few jumps as possible. And how do you know you’ve found them all?

Can you use the information to find out which cards I have used? The fourth article builds on the third by discussing what we mean by problem-solving skills and how NRICH can help children develop these skills.

These upper primary tasks could all be tackled using a trial and improvement approach. Teddy Town Age 5 to 14 Challenge Level: Age 7 to 11 Challenge Level: Investigate the total number of sweets received by people sitting in different positions.

# Addition and Subtraction KS2 :

What questions would you like to ask? Plenty of Pens Age 7 to 11 Challenge Level: Your school has been left a million pounds in the will of an ex- shbtraction.

To support this aim, members of the NRICH team work in a wide range of capacities, including providing professional solcing for teachers wishing to nich rich mathematical tasks into everyday classroom practice. 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?

Sweets are given out to party-goers in a particular way. How many different trains can you make?

## Addition and Subtraction KS1

Can nrichh use the information given to find out how many eggs are in each basket? Use your logical-thinking skills to deduce how much Dan’s crisps and ice-cream cost altogether. Number Balance Age 5 to 7 Challenge Level: Two children made up a game as they walked along the garden paths. Is problem solving at the heart of your curriculum?

This dice train has been made using specific rules. Two children made up a solvung as they walked along the garden paths. There are three baskets, a brown one, a red one and a pink one, holding a total of 10 eggs.

What Could It Be? The Box Game Age 3 to 5 Adding and subtracting. What are the secret jumps they make with their counters? Getting the Balance Age 5 to 7 Challenge Level: History of Money Age 5 to 14 If you would like a new CD you would probably go into a shop and buy one using coins or notes. What numbers of total spots can you make? You might need to do a bit of saving first!