#### NRICH PROBLEM SOLVING NUMBER BONDS

Number Lines Age 5 to 7 Challenge Level: You’ll need two dice to play this game against a partner. Totality for Two Age 5 to 11 Challenge Level: What do you notice about these squares of numbers? Register for our mailing list.

How many different ‘strings’ of numbers add to that total? Can you find some paths of your own? Making Algebra Rich Age 5 to 11 Lynne suggests activities which support the development of primary children’s algebraic thinking. This problem is designed to help children to learn, and to use, the two and three times tables. 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.

Birthday Cakes Age 5 to 7 Challenge Level: You can put more than one weight on a hook. Can you find a pair of numbers that has four odds between them? Learners’ suggestions might include, for example, working top down, or bottom up, or hexagon out, matching colours, making pairs first, noticing the three 5s and therefore reasoning that one of these will have to be on an outer edge How would you test your idea?

The idea is to change the colour of all the spots on the grid.

# One Big Triangle :

Can you use the numbers on the dice to reach your end of the number line before your partner beats you? Odd Differences Age 14 to 16 Challenge Level: The cards are more difficult to arrange than the interactivity because they can be rotated.

My number is problej a multiple of 5 and a multiple of 6. On NRICH there are many more longer investigations which require children to conjecture, convince and prove, and using algebraic notation can often be helpful in the latter.

Getting the Balance Age 5 to 7 Challenge Level: Unit Differences Age 5 to 7 Challenge Level: Can you work out where their counters will land? Exploring the structure of a number square: Using the interactive, place a few triangles in the big triangle, making sure that touching faces add to 10 and ask children to think about what they notice.

The aim of the game: Let us know how you go about trying to make the big triangle.

The idea is to go round the track in as few jumps as possible. George needs 2p more and Jim need 50p more to buy it. Domino Sorting Age 5 to 7 Challenge Level: Andrew decorated 20 biscuits to take to a party. How problsm biscuits weren’t decorated? Can you do it in fewer throws of the dice?

Totality game for an adult and child. You could show the images of the small triangles, or the interactive, solvinv the board and ask children to look in silence for a few minutes and think about what they can see.

# Addition and Subtraction KS1 :

Try out this number trick. Ip Dip KS1 is a well known elimination game similar to one potato, two potato for younger pupils. Can you use the information given to find out how many eggs are in each basket? There are three versions of this challenge.

## 481 Matches for age 3 to 5 for number bonds

Roman Numerals Age 7 to 11 Challenge Level: What happens when you add pairs of the numbers together? What kind of number do you get? Fifteen Age 7 to 14 Challenge 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?