Addition and subtraction

In this investigation, you are challenged to make mobile phone numbers which are easy to remember. What happens if you make a sequence adding 2 each time?

If p is a positive integer and q is a negative integer, which of these expressions is the greatest?

These caterpillars have 16 parts. What different shapes do they make if each part lies in the small squares of a 4 by 4 square?

This Sudoku, based on differences. Using the one clue number can you find the solution?

This Sudoku requires you to do some working backwards before working forwards.

Max and Mandy put their number lines together to make a graph. How far had each of them moved along and up from 0 to get the counter to the place marked?

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?

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

Special clue numbers related to the difference between numbers in two adjacent cells and values of the stars in the "constellation" make this a doubly interesting problem.

Ahmed is making rods using different numbers of cubes. Which rod is twice the length of his first rod?