BODMAS says GO.
We say STOP.
See the structure first. The STOP Method™ replaces rule memorisation with structural understanding — from Year 7 arithmetic to Year 12 algebra.
“BODMAS is a rule. The STOP Method™ is a habit.”
I taught maths for fifteen years
and didn’t see it either.
For most of my teaching career I parsed expressions structurally without thinking about it. I saw terms. I treated brackets as units. I just never had a name for it, and I assumed every reasonably experienced maths teacher saw the same thing.
Then a long-running conversation with a commercial pilot — a fifteen-year friend — changed how I saw my own subject. He talked about aviation the way pilots do: whole picture first, then components. The controller looking at the entire airspace before zooming to one aircraft. The pilot scanning the panel before fixating on a single instrument. Safety as a habit of seeing structure.
That cross-disciplinary lens did something specific. Fragments I had collected over fifteen years of teaching — “treat the bracket as one number”, “division is multiplication by the reciprocal”, “subtraction is just adding a negative” — suddenly fused into a single pattern. The pattern had been sitting in my own teaching the whole time. I just hadn’t been able to name it from inside the field.
The name became the STOP Method™. The fragments became one method.
— Henry Kim, Mathematics Educator & Creator of the STOP Method™
This is also why teachers tend to recognise the STOP Method™ immediately. It is not a critique of teaching. It is a name for what experienced teachers already do — finally made teachable to students.
The research has a name for this
Education researchers call it the expert blind spot (Wineburg 2001; Nathan & Koedinger). Experts in any field internalise patterns so deeply they stop seeing them — which makes those patterns invisible to teach. The STOP Method™ surfaces the pattern that experienced maths teachers were already using subconsciously.
BODMAS teaches students to GO.
Experts do the opposite.
When experts see a complex expression, they don't scan left to right applying rules. They see the structure — independent terms, sealed brackets, operations within. Every curriculum teaches the scanning method. No curriculum teaches the structural method. Until now.
BODMAS approach
- 1. Scan for Brackets → enter (4+1)
- 2. Scan for Orders → find the square
- 3. Scan for Division → find 6÷3
- 4. Scan for Multiplication → find 2×25
- 5. Scan for Addition → find 3+50
- 6. Scan for Subtraction → find 53−2
6 full scans of the expression. Sequential. Fragile.
STOP Method™ approach
- S Seal: (4+1) → treat as one number
- T Terms: 3 | 2×[5]² | 6÷3
- O Operations: 3 | 50 | 2
- P Put together: 3 + 50 − 2 = 51
4 steps. Structural. Each term resolved independently.
Four letters. One principle.
The STOP Method™ works at two levels: a method for order of operations, and a philosophy for all of mathematics.
Seal brackets
Treat bracketed expressions as single units — do not enter yet.
Terms
Separate the expression into independent terms by + and − signs.
Operations within
Within each term: resolve powers first, then multiplication and division.
Put together
Combine all terms via addition and subtraction.
Level 2 — The Philosophy
See The Overall Picture
The same four letters. A principle that extends from Year 7 arithmetic to every topic in secondary mathematics.
Nine error types. One principle.
Every common maths error shares the same root cause: students enter a structure before seeing the whole picture. The STOP Method™ fixes all of them with a single instruction.
Order of operations
Common error
3 + 2 × 4 = 20
With the STOP Method™
3 + 2 × 4 = 11
The STOP Method™ sees two terms: 3 and 2 × 4. No confusion about what comes first.
Expanding solved equations
Common error
(x−3)(x+5) = 0 → x² + 2x − 15 = 0
With the STOP Method™
(x−3)(x+5) = 0 → x = 3 or x = −5
The STOP Method™ says: Seal. The equation is already solved. Do not enter the brackets.
Substitution errors
Common error
x = −3, x² = −3² = −9
With the STOP Method™
x = −3, x² = (−3)² = 9
The STOP Method™ says: Seal the value. (−3) is one unit — wrap it before substituting.
Illegal fraction cancellation
Common error
(x + 3) / (x + 4) → 3/4
With the STOP Method™
(x + 3) / (x + 4) — cannot simplify
The STOP Method™ says: See the terms. x + 3 is a sum, not a product. You can only cancel factors.
Invisible brackets
Common error
(3 + 5) / (3 + 4) — students miss the fraction bar as brackets
With the STOP Method™
The fraction bar IS brackets. Seal the numerator and denominator.
Fraction bars, exponent bases, and distributive law all contain invisible brackets.
Plus 4 more error types covered in the full programme: cross-multiplication, quadratic inequalities, fraction coefficients, and structural parsing.
You already use the STOP Method™.
Your students don't.
As we said in the origin: I had the same view for fifteen years. Most experienced maths teachers already parse expressions structurally — see terms, treat brackets as units, scan the whole picture before any operation. We just never had a name for it, or a way to teach it explicitly.
The STOP Method™ is not a critique of how you teach. It is a name for the expert habit you already use, made teachable to your students.
The teacher test
Show any maths teacher this equation:
Then ask: “Why do students expand this?”
Every teacher knows the student. No teacher has traced the cause to BODMAS. The STOP Method™ does. The “B = Brackets first” reflex trained in Year 7 becomes “enter every bracket” in Year 10.
Free for public schools. Always.
The STOP Method™ teaching resources are free for all public school teachers. Download classroom materials, share with colleagues, use in your lessons. No login required. No strings attached.
Coming soon — teacher resource pack with classroom-ready worksheets and slides.
STOP Method™ Math
A highlight-based app that teaches the structural habit. Short lessons, guest-play friendly, no signup required to start. See the S → T → O → P process in action — whether you're a student, a parent helping at the kitchen table, or an adult quietly rebuilding maths confidence.
Start free
Module 1 first highlights free. No login needed — guest play.
Highlight format
Short, 3–5 minute structural lessons. Learn on the train, during tea, between classes.
Optional sign-in
Apple / Google 1-tap for cross-device sync and streak. Never required.
STOP Method™ Basics
First highlights freeOrder of operations with structural parsing. See terms, not rules.
Invisible Brackets
IncludedFraction bars, exponent bases, and the distributive law made visible.
Cancel Does Not Exist
IncludedFraction simplification by dividing, not "cancelling". Terms vs factors.
Seal Before Substituting
Free updateNegative value substitution with bracket discipline.
Inequalities & Cross-multiply
Free updateQuadratic inequalities by sign reasoning. Fraction comparison without tricks.
$4.99
one-time, lifetime
Unlock all modules. Future modules included at no extra cost.
No subscription. Restore purchase supported. Family Sharing enabled.
For schools: the standalone app is a consumer entry point. Full school deployment runs on the SeedTree platform with teacher workflows, role groups, and curriculum alignment.
Why aviation matters to maths education
The aviation conversation that surfaced the STOP Method™ also points to where the same structural habit matters most. In 1983, Air Canada Flight 143 ran out of fuel mid-flight because of a unit-conversion error. The 767 glided to an emergency landing with 69 passengers on board. The root cause traces back to secondary mathematics.
The STOP Method™ is not just a teaching method. It is upstream safety infrastructure — mathematical thinking that prevents errors before they reach the cockpit, the hospital, or the engineering lab.
Ready for the STOP Method™?
Join the teachers who are replacing rule memorisation with structural understanding.