OCR GCSE Computer Science (J277) – Debugging Mastery (40 Drills G3–9 + Pseudocode Runner + Answers)

40 Structured Run–Fix–Prove Challenges (Grades 3–9)

A complete, ready-to-use debugging system for OCR J277.

This resource includes 40 structured debugging drills AND a fully functional OCR-style pseudocode runner – allowing students to run, test, debug and prove solutions immediately with zero setup.

No planning. No extra tools. Just open and teach.
OCR GCSE Pseudocode Runner

Browser-based (no installation required)

OCR-style syntax

0-based arrays (including 2D arrays)

File handling (virtual file system)

Input in output panel (no pop-ups)

Built-in help and self-tests

Multiple theme options for classroom display

Students can run and debug every task directly inside the runner.
40 carefully structured debugging challenges covering:

Syntax errors

Logical errors

Boundary and indexing mistakes

Validation faults

Function return errors

Array and 2D array bugs

File handling errors

Grade 9 synoptic multi-bug programs

Each task includes:

Bug type checklist

Clear goal

Testing table (Run–Fix–Prove structure)

Explanation section
Teacher Answer Booklet

Fully corrected code for all 40 drills

Clear teacher notes explaining each bug

Marking guidance

Assessment & Intervention Pack

Grade 3–9 rubric

40-task progress tracker

6-lesson intervention outline

Common OCR debugging misconceptions