A short and simple book. Bonds to 20 are pairs of numbers that add together to make 20. This simple book may help to reinforce adding numbers to 20. There are lots of opportunities to challenge your child. You have blank square questions so you can determine if your child knows the missing number to add to make 20. You can consolidate and reinforce your child's knowledge with various simple questions. Do you know your bonds to 20? Do you know your number pairs to 20? Do you know how to count to 20? Help your child to be more confident with bonds to 20. Children in year 1 and year 2 need to know their bonds to 10 and 20.