Lesson Plan

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Lesson Plan
Grade: Date: 17/01/2026
Subject: Computer Science
Lesson Topic: Declare and use one-dimensional and two-dimensional arrays
Learning Objective/s:
  • Describe what an array is and differentiate between one‑dimensional and two‑dimensional arrays.
  • Write correct declaration and initialization syntax for arrays in Java (or Cambridge pseudocode).
  • Access and modify array elements using the appropriate index(es).
  • Implement loops to process arrays (e.g., sum, average, search) while avoiding index‑out‑of‑bounds errors.
  • Apply array concepts to solve typical IGCSE exam tasks.
Materials Needed:
  • Projector and screen
  • Whiteboard and markers
  • Student laptops with a Java IDE installed
  • Printed handout of array syntax and example code
  • Worksheet with practice questions (1‑D and 2‑D arrays)
  • Diagram of a 3 × 4 grid for visualising 2‑D arrays
 Introduction:
Imagine storing an entire class’s test scores in a single variable. Students already know variables and basic loops, so we’ll connect that knowledge to the idea of grouping values in arrays. By the end of the lesson they will be able to declare, initialise, and iterate through both 1‑D and 2‑D arrays, and they will know the success criteria for the day’s activities.
Lesson Structure:
  1. Do‑now (5’) – Quick quiz on variables and loops; students write a simple for‑loop.
  2. Mini‑lecture (10’) – Introduce arrays, show 1‑D declaration/initialisation in Java and pseudocode.
  3. Guided coding (15’) – Students write Java code to sum a 1‑D array; teacher checks understanding with a few questions.
  4. Introduce 2‑D arrays (10’) – Visual diagram of a grid, discuss declaration syntax and element access.
  5. Pair programming (15’) – Create a 3 × 4 matrix, print it, and calculate the total using nested loops.
  6. Common pitfalls & exam tips (5’) – Index bases (0 vs 1), bounds errors, default values.
  7. Independent practice (10’) – Worksheet: write pseudocode for a 2‑D array task and convert it to Java.
Conclusion:
We recap the key steps for declaring, initialising, and iterating through both types of arrays and highlight the index‑base differences. For the exit ticket, each student writes one line of code that accesses a specific element of a 2‑D array. Homework: complete the worksheet converting the provided pseudocode into Java and create a short program that finds the highest value in a 1‑D array.