Lesson Plan

• Describe the concept of arrays and 1‑based indexing in pseudocode.
• Write pseudocode to declare, initialise, and traverse an array.
• Apply common array algorithms (sum, maximum, linear search, insertion) in pseudocode.
• Identify and avoid typical pitfalls such as out‑of‑bounds errors and incorrect accumulator use.
• Test pseudocode solutions with edge‑case scenarios (empty array, single element, full capacity).

• Projector and screen
• Whiteboard and markers
• Printed handouts containing pseudocode templates and practice questions
• Computers or tablets with a simple IDE/pseudocode editor (optional)
• Worksheet with array exercises for pair work

Begin with a quick scenario: “How would you quickly calculate the average of a class’s test scores?” This taps into students’ prior knowledge of loops and variables. Review the idea of an index and remind them that in Cambridge A‑Level pseudocode we start at 1. State that by the end of the lesson they will be able to write correct pseudocode for a range of array operations.

1. Do‑Now (5’) – short quiz on loops and indexing to activate prior knowledge.
2. Mini‑lecture (10’) – introduce arrays, declaration syntax, and 1‑based indexing with examples.
3. Guided practice (15’) – walk through the “sum of all elements” and “find maximum” templates on the board.
4. Pair activity (15’) – students use handouts to write pseudocode for calculating an average and performing a linear search.
5. Whole‑class review (10’) – share solutions, highlight common pitfalls (out‑of‑bounds, accumulator reset).
6. Extension task (10’) – individual challenge: write pseudocode to reverse an array in place.
7. Exit ticket (5’) – each student writes one line of pseudocode to insert a value into an array at a given position.

Recap the key steps for declaring, initializing, and processing arrays in pseudocode, and remind students of the checklist for testing edge cases. Collect the exit tickets to gauge understanding, and assign the three practice questions from the source as homework to reinforce the day’s learning.