This two-digit subtraction game helps second graders subtract numbers within 100 by playing: pop balloons, flip memory cards, race cars or sprint through true and false sentences. Each question takes a number from 10 up to 99 away from a number of 30 or more, such as 82 − 38 or 91 − 47, and some need regrouping while others do not. It is free, needs no sign-up, works on phones and tablets, and comes with a printable sheet showing three ways to subtract two-digit numbers.
Two-digit subtraction game: see how it plays
The two-digit subtraction game below has four modes, and every question subtracts one two-digit number from another. The printable sheet shows a worked example three ways, a counting-up number line, column subtraction with regrouping and a short test, and the pictures show Answer Race, Balloon Pop and Memory Match on this page.
How the two-digit subtraction game works
- Answer Race: every right answer moves your car forward, and you race three computer cars to the finish flag. The first to 15 wins, and wrong taps cost time, not places.
- Balloon Pop: answers float up on balloons, and you pop the right one before it drifts off the top. The wrong balloons are within 12 of the right answer, so children must subtract carefully and cannot pick by size. The game speeds up as your score climbs, and three misses ends the round.
- Memory Match: twelve face-down cards hide six subtraction facts such as 74 − 50 and their six answers. Flip two at a time and match each one to its answer in as few moves as you can.
- True or False: sixty seconds on the clock. Decide whether each sentence, such as 82 − 38 = 44, is right or wrong. A streak of five or more scores double.
Subtracting two-digit numbers: what the game asks
In the two-digit subtraction game the start number is from 30 to 99 and the number taken away is from 10 up to the start number, so the answer is never below zero. That gives 3,885 different questions. About 41 percent need regrouping, which happens when the ones digit of the bottom number is bigger than the ones digit of the top number, as in 82 − 38 where 2 is smaller than 8. The other 2,310 do not need it and are a good place to begin.
Two-digit subtraction with regrouping: eight examples
These eight sample questions show how to decide whether to regroup. Compare the ones digits first: if the top ones digit is smaller, take one ten and turn it into ten ones.
| Question | What to do | Answer |
|---|---|---|
| 76 − 23 | No regroup: 7 − 2 = 5 tens and 6 − 3 = 3 ones | 53 |
| 68 − 35 | No regroup: 6 − 3 = 3 tens and 8 − 5 = 3 ones | 33 |
| 82 − 38 | Regroup: 8 tens and 2 ones becomes 7 tens and 12 ones, then 7 − 3 and 12 − 8 | 44 |
| 91 − 47 | Regroup: 9 tens and 1 ones becomes 8 tens and 11 ones, then 8 − 4 and 11 − 7 | 44 |
| 63 − 28 | Regroup: 6 tens and 3 ones becomes 5 tens and 13 ones, then 5 − 2 and 13 − 8 | 35 |
| 55 − 19 | Regroup: 5 tens and 5 ones becomes 4 tens and 15 ones, then 4 − 1 and 15 − 9 | 36 |
| 70 − 34 | Regroup: 7 tens and 0 ones becomes 6 tens and 10 ones, then 6 − 3 and 10 − 4 | 36 |
| 94 − 56 | Regroup: 9 tens and 4 ones becomes 8 tens and 14 ones, then 8 − 5 and 14 − 6 | 38 |
Two digit subtraction strategies: four ways to subtract 82 − 38
| Method | Steps | Answer |
|---|---|---|
| Count up | 38 + 2 = 40, 40 + 40 = 80, 80 + 2 = 82, so 2 + 40 + 2 | 44 |
| Take away in parts | 82 − 30 = 52, then 52 − 8 | 44 |
| Round and adjust | 82 − 40 = 42, then add back 2 | 44 |
| Column subtraction | Regroup: 7 tens and 12 ones. 12 − 8 = 4, then 7 − 3 = 4 | 44 |
Counting up is the best method when the two numbers are close, such as 91 − 87, because it avoids regrouping completely. Wikipedia’s subtraction article describes the borrowing and counting-up methods.
Check your subtraction with addition
Subtraction and addition undo each other, so any answer can be checked: add the answer back to the number taken away, and the result should be the start number. For 82 − 38 = 44, check 44 + 38 = 82. This check is the best habit for children to learn, because it turns every subtraction into a way to practice addition too. In the two-digit subtraction game, a wrong answer turns the question into a quick check, and a child can try the addition in their head.
Two digit subtraction game and subtraction within 100 practice
Parents often search for a two digit subtraction game, and it means this: a quick, low-pressure way to practice subtraction within 100. Start with a round of five minutes, talk about one question that was hard, and then play again. The two-digit subtraction game remembers your best score on the device, so children can try to beat it.
Subtraction with regrouping game: when the ones are too small
A subtraction with regrouping game needs the child to notice when the ones digit on top is smaller than the one below. In 82 − 38 the 2 is smaller than the 8, so one ten is traded for ten ones and the sum becomes 12 − 8. About 41 percent of the questions in the two-digit subtraction game have this feature, which is why it gives such good practice.
Grade 2 subtraction game and borrowing subtraction game ideas
A grade 2 subtraction game works best after the methods are known, so use it for speed and not for teaching. A borrowing subtraction game is the old name for the same idea, and many parents still use the word borrowing, while schools now say regrouping or trading. Whichever word you use, ask the child to explain what happened to the ten.
Subtraction with regrouping printable: the strategies sheet
The subtraction with regrouping printable shows three strategies side by side with the same worked example, 82 − 38, then a counting-up number line and a column with the traded ten in red. Children can copy the layout for their own questions, and the six practice problems at the bottom have room for the working. Print it for every child, and keep one copy beside the two-digit subtraction game.
Skills to build before two-digit subtraction
- Know the facts to 20: play the subtraction within 20 game.
- Know place value: play the tens and ones game.
- Subtract tens: 80 − 30 is eight tens minus three tens, which is five tens.
- Subtract ones from a two-digit number: 52 − 7 is 52 − 2 − 5.
- Subtract two two-digit numbers with a strategy, then check with addition.
Where two-digit subtraction fits at school
| Level | What children are expected to do |
|---|---|
| Grade 1 (US) | Subtract multiples of 10 from multiples of 10 in the range 10 to 90 (1.NBT.C.6) |
| Grade 2 (US) | Fluently add and subtract within 100 using place value strategies (2.NBT.B.5) |
| Year 2 (England) | Subtract a two-digit number and ones, tens, and two two-digit numbers |
The Common Core grade 2 number and operations in base ten standards name this skill. Print the subtraction worksheets for written practice with answer keys.
Two-digit subtraction game: frequently asked questions
What grade is the two-digit subtraction game for?
Grade 2 in the United States, and Year 2 in England, usually ages 7 and 8.
What is regrouping in subtraction?
It means trading one ten for ten ones when the ones digit on top is too small to subtract from. It is sometimes called borrowing.
How many questions does the two-digit subtraction game have?
There are 3,885 different questions. The answer is never negative.
What is the easiest way to subtract two-digit numbers?
It depends on the numbers. Counting up suits numbers that are close, and taking away in parts suits the others. Column subtraction works for all.
Is the two-digit subtraction game free, and do kids need an account?
Yes, it is free, and no account is needed. Best scores are saved only in the browser on this device.
Does it work on phones and tablets?
Yes. Every game is built for touch first and also works with a mouse on a computer.