Generate a worked example with a deliberate error

Generate a worked example with a deliberate error

Most worked examples are perfect by the time the class sees them, and the kids who follow the perfect ones still cannot find their own mistakes the next day. Faulty-example modelling is the move that fixes this. You show the working with one plausible error planted in it, the kids hunt for it, and the lesson that follows is the one where they explain what wrong looks like in their own words. This prompt drafts the worked example, the error, and the teacher notes in one pass.

The prompt

You are an experienced [SUBJECT] teacher at an Australian [PRIMARY / SECONDARY / TERTIARY] school. Your task is to produce a WORKED EXAMPLE with a DELIBERATE ERROR planted in it, for students to study and then find.

This is not a trick question. The technique is faulty-example modelling: students who study a worked solution and then identify the mistake learn more than students who study a perfect example or who solve a fresh problem cold. The error must be plausible, must come from a real student misconception at this year level, and must NOT be flagged with hints, asterisks, bold text, or "watch out here".

CONTEXT
- Year level: [YEAR LEVEL, e.g. Year 9]
- Subject and topic: [e.g. Year 9 Maths, simultaneous equations by elimination]
- The specific skill or concept the example should model: [e.g. eliminating a variable by adding two equations when the coefficients have opposite signs]
- The misconception I want students to confront: [e.g. forgetting to multiply the entire equation when scaling one row, or adding when they should subtract]
- Class context: [anything that matters, e.g. EAL/D learners need short sentences, or mixed-ability Year 9]

WHAT YOU WILL PRODUCE

1. THE WORKED EXAMPLE (student-facing)
   - Set out the problem.
   - Show the full working step by step, the way a student would see it.
   - Place ONE deliberate error in the second half of the working, after at least three correct steps.
   - The error should produce a wrong-but-plausible final answer, not an obvious nonsense answer like a negative length or an unbalanced equation that is visibly absurd.
   - Use Australian conventions and ACARA v9.0 vocabulary.

2. THE STUDENT TASK (one sentence)
   - Tell students what to do (e.g. "Find the line where the working first goes wrong, and explain in one sentence what the student was thinking when they wrote it.").

3. THE TEACHER NOTES (clearly separate from the student-facing material)
   - The line number where the error sits.
   - The misconception it models, named in one sentence.
   - Your estimate of the percentage of students at this year level who will spot it without help.
   - One stretch question for the kids who spot it fast, so they are not idle.
   - One scaffold question for the kids who cannot find it after three minutes.

Do not write any other commentary. No introduction, no "I hope this helps".

What it does well

It generates the artefact students see AND the teacher script that goes with it (line of the error, misconception named, follow-up questions for the fast finishers and the stuck kids). That second half is the bit a teacher rarely writes from scratch on a Wednesday afternoon, and it is exactly what makes the technique work in a real classroom.

Where it falls over

AI tends to put the error somewhere the strongest kids will spot in 15 seconds. Eyeball the working before you print, and if the error is on line two, rewrite it into the middle of the solution where it has to survive a few correct steps. The other failure: the misconception named is sometimes generic ("students forget the negative sign") rather than the misconception your class actually holds. You still have to bring the diagnostic eye yourself.

Try it like this

For Year 9 maths: simultaneous equations by elimination, with the error placed on the line where the coefficients are scaled before adding.

For Year 11 English: a literary-analysis paragraph where the quote is correctly placed but the inference drawn from it does not actually follow. Students mark up the quote-to-inference link, not the writing.

For Year 8 science: a balanced equation that fails to conserve mass on one side. Cleanest pivot to a follow-up lesson on the law of conservation of mass.

Run this in the last fortnight of Term 2 as part of revision and your class will own the misconceptions before the holidays. Run it in week one of a new topic and they walk into the unit with the wrong answer already debugged.