Use the language of addition and subtraction
Using the correct mathematical vocabulary will get your child used to deconstructing word problems, and will make them familiar with the kinds of words they will hear in school.
Try to use mathematical language like add, altogether, more, plus, total, and sum when adding. When your child finds the answer to an addition calculation, encourage them to use the word total or sum. If they talk about the fact that you can add numbers in any order and get the same answer, encourage them to use the word commutative.
There is also a lot of mathematical vocabulary related to subtraction. When your child tells you the answer to a subtraction calculation, encourage them to refer to this as the difference. For example, ‘7 – 3 = 4’ could be read as ‘the difference between 7 and 3 is 4’. They should also try to use the language take away, subtract, minus, less, fewer, and so on.
Try writing out the addition and subtraction symbols (‘+’ and ‘–’) along with the related words on cards (for example, add, altogether, more, plus, total, sum, take away, subtract, minus, less, and fewer). Help your child to link the words to the correct symbol. If necessary, help them to read some of the words.
Play the Addition and Subtraction Facts game
Encourage your child to practise addition and subtraction to 20. This will help them derive related facts such as:
3 + 7 = 10
10 – 7 = 3
7 = 10 – 3.
Once they’ve done this, they should be able to use their knowledge of place value to calculate more facts:
30 + 70 = 100
100 – 70 = 30
70 = 100 – 30.
Try lots of different methods
Encourage your child to use a range of methods, including using objects, drawings, diagrams, and symbols, to solve addition and subtraction problems. To solve addition problems, your child might:
To solve subtraction problems, your child might:
It can also be helpful to use more than one method to double-check calculations. For example, your child could check a subtraction question by adding up the answer and the number they subtracted to see if they get back to the number they started from. We call this using the inverse.
Make up story problems
Story problems can be a fun way to help your child understand addition and subtraction and you can have fun making them up! Why not see if your child would like to create a story problem for you?
When creating an addition story problem, you could support your child by giving them objects to use or a picture to inspire their story. Once they’ve completed the word problem, ask them if they could write the calculations in the problem using symbols +, –, and =.
Try missing number problems
Missing number problems can be quite tricky for children. You can support your child by making the most of opportunities to practise missing number problems practically. For example, you can ask for your child’s help if you have a number of something but need a higher number:
‘I have 5 buttons but I need 15 buttons. How many more do I need?’
Ask your child how they worked it out. Then, you could ask them to write a calculation using numbers and symbols to explain how they did it.
5 + ? = 15.
They could have counted on from 5 to 15 to get 10.
They could have counted back 5 from 15 to get 10.
They may have known that 15 – 5 = 10.
… and so on.