Make sure the foundations are solid
Long division leans on three earlier skills: times tables, subtraction with regrouping, and place value. If any of these is shaky, fix it first , otherwise long division will feel impossible no matter how clearly you explain the steps.
Use the divide,multiply,subtract,bring down cycle
Every step of long division is the same four moves, repeated: Divide, Multiply, Subtract, Bring down. Many teachers use a mnemonic (Does McDonald's Sell Burgers?) so children remember the order.
- Divide: how many times does the divisor go into the current digits?
- Multiply: that answer times the divisor.
- Subtract: take it away to find the remainder so far.
- Bring down: the next digit, and repeat.
Start small, then scale up
Begin with no remainders and a single-digit divisor. Once the cycle is automatic, add remainders, then larger numbers, then decimals. Keep the divisor small while the method is new.
Common mistakes
- Forgetting to bring the next digit down.
- Misaligning digits so place value goes wrong.
- Skipping a zero in the quotient when the divisor doesn't fit.