Memorizing math facts can be extremely difficult for some children. If this is the case with your child, there are some tips and tricks you can show them to help them remember some of the basic subtraction facts.
Subtracting one or two from another number can be accomplished simply by counting backwards from the starting number. If the problem is 7 – 2, your child would start at 7 and count backwards two more spots (7, 6, 5). This allows them to arrive at the right answer (5) without having to memorize the fact.
It is also helpful to point out to children that when you have two numbers that are the same in a subtraction problem, the answer is always 0. No matter what number you start with, if you take away the same number (all of what you started with), you are left with 0.
The opposite of subtracting all is subtracting none. When you take away nothing (0) from a number, the answer is always the same number that you started with. The strategies of subtracting all and subtracting none may seem obvious to adults, but many children will not see patterns like this until it has been pointed out to them. Just showing your child that these strategies work for any number will help them understand those subtraction facts better.
This is a set of subtraction facts that many children have a hard time with. One helpful method is to teach your child to subtract 10 from the number to start. Once they have that answer, simply add 1 back to the answer which gives them the correct answer. For example: 17 – 9 = Think 17 – 10 = 7. Then think 7 + 1 = 8. You have now arrived at the correct answer, 8. Although it seems like a little more thought, it is definitely shorter than counting back by nine in their head or on their fingers!
Subtraction Facts are Tricky
Subtraction facts are tricky, but they can be made easier in many ways. Teach your child these strategies, and they will have an easier time with subtraction in general.
How do you help your child remember their subtraction facts?