Year 6 factors and prime number games Many children in Year 6 will still be uncertain about factors and prime numbers. One way of thinking of factors is to say that a factor is a whole number which divides exactly into another whole number, leaving no remainder. So 3 is a factor of 12 because it divides exactly into 12 (12 ÷ 3 = 4 with no remainder). Another way to describe factors is to say that factors are whole numbers you can multiply together to make another whole number. 3 x 4 = 12 so 3 and 4 are factors of 12. This also means that 1 and 12 are factors of 12 as 1 x 12 = 12 and 6 and 2 are factors of 12 as 6 x 2 = 12 A prime number is a whole number which has only two factors. These factors are 1 and the number itself. No other numbers will divide exactly into a prime number. The first few prime numbers are: 2,   3,   5,   7,   11,   13,   17 and 19 Note that 1 is not considered a prime number and that 2 is the only even prime number. Now this might all seem a little bit dull, but we have just published four great games where spotting prime numbers and factors come to life. In our year 6 games: Factors and Prime Numbers we have: Recognising factors Recognising prime numbers Factors of 24 Factors of 48 My favourite is Factors of 48 where numbers pop up on the screen and need clicking if they are factors of 48, before disappearing after a few seconds. These games are especially useful for children who have been introduced to factors and prime numbers before but have struggled to understand them. Go to Factors and Prime Numbers games