Is this algebra? My child is seven.

It is the idea algebra is built on, which is why it belongs at seven rather than later. The game is aimed at grades 2 to 4 and never uses a letter: the blank is just a number nobody has named yet, and keeping both sides equal is the whole method they will later use on x.

Why does the blank sometimes come first, as in __ + 5 = 12?

On purpose. Reading left to right and expecting the answer at the end is exactly the habit that makes older children stumble. Moving the blank around forces a child to work out what the equation says instead of where the answer usually sits.

Does he need subtraction before he can do this?

No. Counting up from the number shown to the total solves every problem here using only addition. Subtraction is a second route that becomes faster later, but a child who has not met it can play this today.

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Balance It

Find the missing number.

Grades 2-4 · The meaning of the equals sign

How to play

1An equation appears with a blank, like 7 + __ = 12.
2Tap the number that makes both sides equal.
3Equals means the two sides weigh the same, not "here comes the answer".
4Keep the scale balanced to grow your streak.

Try a few

9 + __ = 15
Answer: 6
Do not look for a sum, look for the gap. Put a finger on 9 and climb to 15, counting the steps and not the numbers: ten, eleven, twelve, thirteen, fourteen, fifteen. Six steps, so the left side needs 6 to weigh what the right side weighs.
__ + 4 = 11
Answer: 7
The blank moved to the front, but nothing else changed. Both sides still have to come to 11 and one side already shows 4, so climb from 4 to 11: seven steps. Check it in one line, 7 + 4 = 11.
6 + __ = 13
Answer: 7
Go by way of ten. 6 needs 4 to reach 10, and 10 needs 3 more to reach 13. The blank covers both hops, so it is 4 and 3 together: 7.

Why this game helps

Ask a child what goes in 8 + __ = 12 and a surprising number answer 20, because they read the equals sign as "write the total here", the way it works on a calculator. But equals means the two sides are the same amount, a balance, and that reading is the doorway to all of algebra, where x is just a missing number that keeps the scale even. Solving for the blank, with both sides in view, retrains the equals sign from an instruction into a statement of balance. It is a small idea that quietly decides whether algebra later feels natural or impossible.

If your child finds this hard

The wrong answer to watch for is the one already printed. Shown 6 + __ = 13, a lot of children answer 6, and shown __ + 4 = 11 the same child answers 4. It is not carelessness. The visible number is the only thing on the line they feel sure of, and with four buttons on screen the one they can already see feels safest. Nothing is missing from the arithmetic; they have no procedure for a blank and are reaching for something familiar.

Give them the procedure and the guessing stops. Start at the number you can see, count up to the total, and the answer is the number of steps you took, not the number you landed on. Count the steps on fingers, one finger per hop, then read the fingers. It feels slow for a week and then it does not.

If counting on is itself shaky, the blank is not the problem and this will be a grind. Number Line Jump makes the hops visible one arc at a time, and Make Ten builds the bridge the harder equations here lean on.

Common questions

Is this algebra? My child is seven.: It is the idea algebra is built on, which is why it belongs at seven rather than later. The game is aimed at grades 2 to 4 and never uses a letter: the blank is just a number nobody has named yet, and keeping both sides equal is the whole method they will later use on x.
Why does the blank sometimes come first, as in __ + 5 = 12?: On purpose. Reading left to right and expecting the answer at the end is exactly the habit that makes older children stumble. Moving the blank around forces a child to work out what the equation says instead of where the answer usually sits.
Does he need subtraction before he can do this?: No. Counting up from the number shown to the total solves every problem here using only addition. Subtraction is a second route that becomes faster later, but a child who has not met it can play this today.

Try these next

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