### PROBLEM SOLVING KS2 NRICH

Can you discover its value in each problem? Use your addition and subtraction skills, combined with some strategic thinking, to beat your partner at this game. This challenge is a game for two players. If we number the cubes from the top, starting with 1, can you picture which cubes are directly below this first cube? Every card he revealed had the same value as the one he had just finished spelling. Have a go at this well-known challenge.

Subtraction Surprise Age 7 to 14 Challenge Level: Tim had nine cards each with a different number from 1 to 9 on it. Find the chain which contains the smallest possible numbers. Shaping It Age 5 to 11 Challenge Level: Multiplication Squares Age 7 to 11 Challenge Level:

What could the half time scores have been in these Olympic hockey matches? Can you fill in this table square?

In her article Developing Excellence in Problem Solving with Young LearnersJennie Pennant suggests that as teachers we can xolving children get better at problem solving in three main ways, one of which is through ‘explicitly and repeatedly providing children with opportunities to develop key problem-solving skills’. Roll two red dice and a green dice.

Mystery Matrix Age 7 to 11 Challenge Level: Register for our mailing list. Strike it Out Age 5 to 11 Challenge Level: Amy has a box containing domino pieces but she does not think it is a complete set.

Can you get four in a row? Can you replace the letters with numbers? Can you use the information to find out which cards I have used?

# Problem Solving :

Factor-multiple Chains Age 7 to 11 Challenge Level: Choose two of the numbers to multiply or divide, then mark your answer on the number line. Each light in this interactivity turns on according to a rule. To support this aim, members of the NRICH team work in a wide range of capacities, including providing professional development for teachers wishing to embed rich mathematical tasks into everyday classroom practice.

Maze Age 7 to 11 Challenge Level: Always, Sometimes or Never? Factor track is not pronlem race but a game of skill. To support this aim, members of the NRICH team work in a wide range of capacities, including providing professional development for teachers wishing to embed rich mathematical tasks into everyday classroom practice.

These activities focus on finding all possible solutions so working in a systematic way will ensure none are left out. Abundant Numbers Age 7 to 11 Challenge Level: If you know os2 numbers that come out, what multiplication might be going on in the box?

## Problem-solving Skills

One block is needed to make an up-and-down staircase, with one step up and one step down. Can you work out how to win this game of Nim? Try with different steps and see if you can predict what will nrlch. This big box multiplies anything that goes inside it by the same number. They are each holding a card with a number on it.

The fourth article builds on the third by discussing what we mean by problem-solving skills and how NRICH can help children nfich these skills. Explore Alex’s number plumber.

## Working Systematically at KS2

How many shapes can you build from three red and two green cubes? Multiplication and Division KS2. These lower primary tasks could all be tackled using a trial and improvement approach.

Make Age 7 to 11 Challenge Level: This game can replace standard practice exercises on finding factors and multiples. What can you say about these shapes? Factor Track Age 7 to 14 Prolbem Level: Age 5 to 7 Visualising at KS1 These lower primary tasks all specifically draw on the use of visualising.