Addition and subtraction

problem
Play to 37

Age

7 to 11

Challenge level

In this game the winner is the first to make the total 37. Is this a fair game?
problem
Journeys

Age

7 to 11

Challenge level

Investigate the different distances of these car journeys and find out how long they take.
problem
Sums and differences 1

Age

7 to 11

Challenge level

This challenge focuses on finding the sum and difference of pairs of two-digit numbers.
problem
Sums and differences 2

Age

7 to 11

Challenge level

Find the sum and difference between a pair of two-digit numbers. Now find the sum and difference between the sum and difference! What happens?
game

First connect three for two

Age

7 to 11

Challenge level

First Connect Three game for an adult and child. Use the dice numbers and either addition or subtraction to get three numbers in a straight line.
problem
Folded number line

Age

7 to 11

Challenge level

When I fold a 0-20 number line, I end up with 'stacks' of numbers on top of each other. These challenges involve varying the length of the number line and investigating the 'stack totals'.
problem
Sticky dice

Age

7 to 11

Challenge level

Throughout these challenges, the touching faces of any adjacent dice must have the same number. Can you find a way of making the total on the top come to each number from 11 to 18 inclusive?
game

Sumo

Age

7 to 11

Challenge level

A number game requiring a strategy.
problem
True or false?

Age

7 to 11

Challenge level

Without doing lots of calculations, can you decide which of these number sentences are true? How do you know?
problem
Mathdoku

Age

7 to 11

Challenge level

Complete the Mathdoku grid using the clues. Can you convince us that the number you have chosen for each square has to be correct?