Step 4 Objective

Recognise and use multiples, factors and primes (less than 100).

Examples of what pupils should know and be able to do

Probing questions

Which numbers less than 100 have exactly three factors?

What number up to 100 has the most factors?

The sum of four even numbers is a multiple of four. When is this statement true? When is it false?

Can a prime number be a multiple of 4?

What if pupils find this a barrier?

Model the activity below for pupils; list some possible descriptions of numbers, using the targeted vocabulary.

Pupils work in threes. One chooses a number from a set provided (e.g. 14, 24, 25, 40, 64, 99) and describes their number using either the word factor or multiple. The remaining pair of pupils select the possible numbers from the list and then devise their own question(s) to ensure they select the right number.