How to check math homework without doing it for your kid
Grades 1–65 min read
You look over the worksheet, spot a wrong answer, and the fastest thing to do is say “that should be 335.” Your child writes it down, the page is finished, and nobody learned anything.
Checking homework well is a different job from doing it. The goal is for your child to find the mistake, because finding it is most of the learning. Here is how to check quickly and what to say when something is off.
What your job actually is
Homework is practice, and it also tells the teacher what your child can do on their own. If you correct every answer, the teacher sees a perfect page and has no idea that carrying is still shaky.
So your job is not to make the page right. It is to notice whether your child understands, point them toward their own mistakes, and tell the teacher if something is clearly not clicking.
That takes a bit of pressure off you too. You do not need to remember how to do long division perfectly. You need a few ways to check an answer and a few good questions.
Four quick ways to check an answer
1. Estimate
Round the numbers and see if the answer is in the right neighborhood. For 58 × 7, think 60 × 7 = 420. If the page says 406, that is close. If it says 3556 or 65, something went wrong.
Estimating catches the big mistakes: a missing placeholder zero, numbers lined up wrong, adding instead of multiplying. And it is a skill your child can learn to do on their own.
2. Use the opposite operation
Subtraction can be checked with addition. If 724 − 389 = 335, then 335 + 389 should give back 724. It does.
Every step, the way the pad explains it
- Subtract the ones: 4 is smaller than 9, so borrow. Take 1 from the tens: 2 becomes 1, and 4 becomes 14. Now 14 − 9 = 5. Write 5.
- Subtract the tens (now 1 after borrowing): 1 is smaller than 8, so borrow. Take 1 from the hundreds: 7 becomes 6, and 1 becomes 11. Now 11 − 8 = 3. Write 3.
- Subtract the hundreds (now 6 after borrowing): 6 − 3 = 3. Write 3.
Division can be checked with multiplication. If 96 ÷ 8 = 12, then 12 × 8 should be 96. With a remainder, multiply and add it on: for 100 ÷ 8 = 12 R 4, check that 12 × 8 + 4 = 100.
3. Look at the last digit
For addition, subtraction and multiplication, the ones digit of the answer depends only on the ones digits of the numbers. In 58 × 7, the ones are 8 × 7 = 56, so the answer must end in 6. That is a ten-second check.
4. Look for patterns in the wrong answers
One wrong answer is a slip. Three wrong answers that all involve a zero in the top number are a pattern. Patterns are the useful thing to notice, and the thing to mention to the teacher.
What to say when an answer is wrong
Try not to say which answer is wrong, at least at first. Say how many are wrong and let your child hunt.
- “Two of these need another look. Can you find them?”
- “Can you check this one by doing it the other way?”
- “Talk me through this one. What did you do first?”
- “About how big should this answer be?”
- “Which column did you start with?”
Asking them to explain is the most powerful one. Kids very often catch their own mistake halfway through explaining it. Your job is just to listen.
When you do not know the method they are using
Many parents learned one way to multiply or subtract, and the worksheet shows another. That is fine. You do not have to know the method to check the answer. Estimation and the opposite operation work no matter how the problem was solved.
If you want to understand the method, ask your child to teach it to you. It is great practice for them, and you will learn what the class is doing. Our guides to carrying, borrowing across zeros, multi-digit multiplication and long division explain the common school methods in plain language.
Try not to teach a different method the night before a test. Two methods at once is confusing. Once the class method is solid, showing them another way can be fun.
A simple homework routine
- 1Your child does the whole page on their own first, while you are nearby but busy.
- 2They check two or three answers themselves, by estimating or working backwards.
- 3You look over the page and say how many need another look.
- 4They find and fix those. You ask them to explain one.
- 5If the same kind of mistake keeps coming up, write a short note for the teacher.
This takes a little longer than fixing answers yourself for the first week or two. After that it is usually faster, because your child starts checking before they hand the page to you.
How MathPad helps with checking
In MathPad, every digit your child types on the pad is saved with the problem, so in parent view you can see where the work went sideways, not just the final answer. Calculator mode shows a problem fully solved, step by step, so you can check an answer without working it out on scrap paper. You can also adjust marks and leave a note.
While your child works, the guide checks each digit and gives a hint on a wrong step rather than the answer, which is the same approach this post recommends. More on what parents can do is on the MathPad for parents page.
Questions parents ask
- Should I correct my child’s math homework?
- Point out that something needs another look, but let your child find and fix it. The teacher learns more from homework your child did on their own, mistakes included.
- What if I do not understand the way the school teaches it?
- You can still check answers by estimating or by working the problem backwards with the opposite operation. Asking your child to teach you the method is good practice for them too.