11+ Arithmetic Help: Why Your Child Keeps Getting Stuck (And What Actually Works)

Your child gets the method right and the answer wrong. A dropped carry, a forgotten exchange, or a calculation worked left to right when it should not have been.

I'm Aadam, and I've taught arithmetic to hundreds of KS2 and 11+ students at SHLC. It is the least glamorous topic on the syllabus and the one that quietly decides how every other topic goes.

The real problem isn't effort

Parents usually tell me their child just needs to be quicker, or more careful. Neither is quite right.

Fractions, percentages, ratio and algebra are all these same four operations wearing a different hat. A child who is slow at short division is not slow at division, they are slow at everything that contains a division, which is most of the paper. The arithmetic gap does not stay in the arithmetic questions.

And on the non-calculator paper, which is a third of the marks at GCSE and almost the whole thing at 11+, there is nowhere to hide.

What actually goes wrong is usually one of these.

The method was never solid. Not rusty, never secure. A child who is unsure where the carry goes will place it inconsistently, and no amount of repetition fixes a method that was half-learned.

They do not know when to use which method. Some subtractions are far quicker mentally than in columns. A child who columns everything wastes minutes they need elsewhere.

They work left to right. 36 minus 27 plus 8 does not mean what they think it means. This is not carelessness, it is not knowing the rule.

Why worksheets alone don't fix it

Daily arithmetic practice keeps a method sharp. It does not build one that was never there.

If your child sets out a column subtraction wrongly, twenty of them means twenty wrong answers and twenty repetitions of the wrong habit. They mark it, see a low score, and conclude they are bad at maths. The worksheet never showed them where the exchange goes.

The second gap is that worksheets almost never test the choice. Real papers mix everything, and deciding whether to do something mentally, in columns, or by rounding and adjusting is a skill that only gets practised when the question types come jumbled.

The arithmetic skills that trip children up, in order

These build on each other, and the order matters more here than in most topics.

1. Mental addition and subtraction. Bonds to ten, then to a hundred, then to a thousand, and knowing which method suits which question.

2. Column addition and subtraction. Setting out, carrying, and exchanging across a zero, which is the single hardest step in primary arithmetic.

3. Times tables and divisibility. Not just recall. The divisibility tests for 2 to 12 are what make simplifying fractions and finding factors quick rather than laborious.

4. Grid and column multiplication. Including long multiplication and the zero on the second row, which gets dropped constantly.

5. Short division. Remainders, exchanging into the next column, and two-digit divisors.

6. Squares, cubes and roots. Rapid recall plus estimating roots that are not exact.

7. Order of operations. BIDMAS, and specifically that divide and multiply share a rank rather than divide coming first. This one misconception costs more marks than almost anything else on this list.

8. Inverse operations and brackets. Turning exam wording into a calculation, working backwards, and deciding where the brackets go.

What actually closes the gap

Watch them do one, do not just mark twenty. Sit and watch a single column subtraction. You will see the exact moment it goes wrong, and it is almost always the same moment every time. Marking a finished page tells you it was wrong but not where.

Fix the method before adding speed. Speed on a broken method just produces wrong answers faster. Get it right slowly, then time it.

Ask which method before they start. Mentally, in columns, or by rounding and adjusting? Making the choice conscious is what stops a child columning 1000 minus 998.

Teach BIDMAS as four rows, not six letters. Brackets, then indices, then divide and multiply together, then add and subtract together. Children taught it as six separate steps genuinely believe division comes before multiplication.

The lessons we built to fix this

Our Four Operations, Powers and BIDMAS Bundle covers that whole list in order. Eight interactive lessons, 54 units, 766 questions.

Mental Addition and Subtraction and Column Addition and Subtraction cover the first two, including choosing the method and exchanging across zeros.

Divisibility and Multiplication Rules covers recall plus every divisibility test from 2 to 12.

Grid and Column Multiplication and Short Division cover the written methods up to three digits by three digits and two-digit divisors.

Squares, Cubes and Roots covers rapid recall and estimating roots.

Order of Operations (BIDMAS) teaches the ladder as four rows, with divide and multiply sharing a rank, and Inverse Operations and Inserting Brackets covers working backwards and bracket placement.

There are 25 hands-on tools across the bundle. A column builder where one click reveals the carry exactly where a pencil would put it. A bridging number line showing why 47 plus 26 is easier as a hop to 50 then a hop of 23. A missing digit detective that highlights the column it is asking about. A divisibility machine that runs any test and lights up the digits it looks at. A cube that builds one layer at a time, so a child who has made four cubed out of layers stops writing twelve.

Answers stay hidden until clicked, and most question banks deal a fresh set on demand, so a child can repeat a method without repeating the same numbers.

Arithmetic sits second in the teaching order because everything else on the paper rests on it. If more than one block needs work, The Complete 11+ Maths Course covers all 80 lessons for £200 rather than £479.20 bought separately.

What to do this week

Give your child one column subtraction that needs exchanging across a zero. Something like 4,003 minus 1,876. Sit and watch them do it rather than marking it afterwards.

If the exchange goes wrong, that is your fortnight's work and it is a narrow, fixable thing.

Then write 20 minus 4 times 3 and ask for the answer. If you get 48, they are working left to right and BIDMAS is the gap. If you get 8, that part is secure.

For follow-up practice, the free four operations practice page moves from two-digit mental sums at Level 1 to long multiplication and BIDMAS with powers at Level 3, with the answers ready to check.

If you want the full sequence taught in order rather than drilled from worksheets, the Four Operations, Powers and BIDMAS Bundle covers all eight, or you can buy the single lesson your child is stuck on. If you would rather someone looked at where they actually stand first, book a free consultation and we will talk it through.

Our guide to 11+ maths at home has a question you can read out to check this topic, plus where children get stuck in the other 15 areas of 11+ maths and what to try.

Aadam, SHLC Tutors