OCR GCSE Computer Science J277 Debugging Mastery Workbook – 21 Tasks, Timed Test & Mark Scheme

OCR GCSE Computer Science J277 Debugging Mastery Workbook – 21 Tasks, Timed Test & Mark Scheme

Turn your students into confident, exam-ready debuggers — in one resource.

Debugging is the skill that quietly costs GCSE Computer Science students the most marks — and the one teachers have the least ready-made material for. This 29-page workbook fixes that, completely.

Built specifically for OCR GCSE Computer Science (J277), this is a full progression from first-attempt “spot the missing colon” tasks right through to the kind of subtle, multi-layered bugs that separate a Grade 7 from a Grade 9. Every single task follows a rigorous 10-part structure — faulty code, student task, marks available, error identification, why it happens, corrected code, explanation of the fix, test data, expected output, AND the common misconception behind it — so students don’t just fix the bug, they understand it deeply enough to never make it again.

• What’s inside:

21 fully worked debugging tasks in Python and OCR Exam Reference Language (pseudocode)
6 progressive sections: Find the Error → Explain the Error → Fix the Code → Find Multiple Errors → Debug Under Exam Conditions → Grade 9 Debugging Challenges
All 19 error categories on the spec covered: syntax, logic, runtime, incorrect conditions/loops, off-by-one, incorrect variable updates, incorrect data types, input-handling, selection, iteration, function/procedure, array indexing, algorithmic, Boolean logic, boundary conditions, infinite loops, incorrect initialisation, and incorrect output
A 30-minute, 40-mark Timed Debugging Assessment — genuine exam conditions
A complete, examiner-style mark scheme with accepted alternative answers and grade boundary guidance
Clean, professional formatting — projector-ready or print-ready, straight out of the box

Why teachers love it:

Saves hours of resource-writing time — this is a term’s worth of debugging practice, done for you
Perfect for starters, homework, revision lessons, cover lessons, or a dedicated “Debugging Week”
Genuinely stretches your top-set students with Grade 9-level challenges most resources don’t attempt
Built-in misconception boxes mean less re-teaching and faster progress
Works for whole-class teaching, independent revision, or 1:1 intervention

If your students can write code but panic the moment they’re handed someone else’s broken program, this is the resource that changes that — permanently.

Grab it now and give your Computer Science classes the debugging fluency examiners are actually looking for.

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