Algorithms. Full Lesson Pack. Worksheet + Homework + Answers. Includes Algorithm Efficiency
Full lesson pack with worksheet, homework and answers
Focus: Algorithm, instruction, sequence and efficiency
This is a complete, carefully structured lesson introducing KS3 / beginner students to the concept of an algorithm as a clear, step-by-step description of a process.
The lesson is designed for Key Stage 3 students and has been built to avoid overly simplistic or patronising examples. It builds strong conceptual foundations.
What this resource includes:
Full PowerPoint lesson (explicit and suitable for revision)
Student worksheet
Differentiated homework task
Full teacher answer sheet
Teacher notes outlining structure, timing and pedagogy
Content covered:
Definition of an algorithm
The meaning of instruction and sequence
Evaluating weak algorithms using technical vocabulary
Writing clear, structured algorithms for real-world tasks
Introduction to best case, worst case and average case
Early thinking about algorithm efficiency
The lesson deliberately moves beyond “does it work?” to begin exploring “does it work well?”, using a structured search scenario to introduce efficiency in an accessible way.
Pedagogical approach:
Explicit teaching of technical vocabulary
Structured discussion and evaluation
Scaffolded writing tasks
Clear model answers
Stretch through efficiency analysis
This lesson forms a strong foundation for later work on conditionals, loops, flow diagrams and programming in Python.
Suitable for:
Key Stage 3 Computer Science
Non-specialist teachers
Schools introducing algorithms before programming
All materials are editable.



