Handling built-in exceptions lesson for Pearson Edexcel International A Level Computer Science, with editable PowerPoint slides, a student worksheet and full answers. Exception handling lets a Python program cope with errors without crashing; students use try and except for bad input and missing files.

Written for Unit 2 Practical Programming, topic 7 Programming (specification 7.1.1 e, 9.2.3 b). Everything is editable, so you can adapt it to your class.

What’s included

• PowerPoint lesson (15 slides) with teacher notes on every slide
• Student worksheet (Word), ready to print or edit
• Answer sheet (Word) with mark-scheme style answers for every question

U2.03 Handling built-in exceptions

By the end of the lesson students can:

• Identify the built-in exception that a line of code raises
• Write try/except blocks that name the exceptions they handle
• Use exception handling to keep a program running after bad input

Worksheet sections: A. Identify the exception; B. Predict the output; C. Amend the code; D. Exam-style question; E. Challenge

Every lesson includes

• Learning goals and a starter question
• Clear explanations, diagrams and worked examples (Python 3 throughout, as the specification requires)
• A quick check and a “your turn” task linked to the worksheet
• Exam-style questions with marks, and an exit ticket

Format

• PowerPoint (.pptx) and Word (.docx), fully editable
• Works in PowerPoint and Google Slides
• Calm, muted sixth-form design, consistent across the whole course

These are independent resources written for the Pearson Edexcel International Advanced Level Computer Science specification (Issue 1, first teaching 2026; IAS XCP01, IAL YCP01). They are not produced or endorsed by Pearson.

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• Previous lesson: Count- and condition-controlled loops – Edexcel IAL CS lesson
• Next lesson: Variables, constants and operators – Edexcel IAL Computer Science
• Save with the bundle: Programming – Edexcel IAL Computer Science (5 lessons)

Last updated: November 2026.