Unplugged Computational Thinking

A three-year sequence of unplugged lessons designed to develop computational and algorithmic thinking from Year 7 through Year 9. The progression moves students through three distinct phases: from executing instructions with precision, to designing solutions before coding, to reasoning about data and efficiency. Each year is built around a unifying theme and culminates in skills that prepare students for formal programming and computer science study.

All lessons are 50 minutes, student-activity-focused, and deliverable by non-specialist teachers.


Year 7 — The Instruction Manual

Students learn to think like a machine, building fluency in the fundamental building blocks of computation.

Theme: Computers are literal — they do exactly what you tell them, nothing more.

Skills: Algorithms, Sequence, Variables, Iteration, Selection, Flowcharts, Debugging, Nested Structures.


Lesson 1 — The “Robot” Teacher

Writing precise sequential instructions by commanding a literal-minded teacher-robot.

Lesson Plan · Slides · Worksheet: Instruction Sheet


Lesson 2 — The Memory Box

Understanding variables and state by tracing values through a narrative scenario.

Lesson Plan · Slides · Worksheet: Variable Trace · Resource: Variable Labels


Lesson 3 — The Loop Dance

Using for loops and while loops to write efficient, repetitive dance routines linked to changing counter variables.

Lesson Plan · Slides · Worksheet: Dance Designer


Lesson 4 — The Maze Game

Navigating a partner through a physical grid maze using IF/ELSE decisions and recording solutions as flowcharts.

Lesson Plan · Slides · Worksheet: Flowchart · Resource: Maze Grid · Resource: Trigger Cards


Lesson 5 — Bug Hunters

Diagnosing and fixing deliberate errors in pre-written algorithms to develop systematic debugging skills.

Lesson Plan · Slides · Worksheet: Buggy Algorithms


Lesson 6 — The Grand Challenge

Solving a complex maze under a line limit, requiring nested loops and conditionals working together.

Lesson Plan · Slides · Worksheet: Solution Sheet · Resource: Challenge Maze


Year 8 — The Architect

Students learn to think like an engineer, shifting focus from executing instructions to planning and structuring solutions.

Theme: Solving the problem before you write the code.

Skills: Decomposition, Pattern Recognition, Abstraction, Boolean Logic, Evaluation, Functions.


Lesson 1 — Zombie Survival Plan

Decomposing a large, vague problem into a hierarchy of small, actionable sub-tasks.

Lesson Plan · Slides · Worksheet: Hierarchy Tree


Lesson 2 — Spot the Pattern

Identifying shared structures across different problems and writing a single generalised solution template.

Lesson Plan · Slides · Worksheet: General Algorithm · Resource: Scenario Cards


Lesson 3 — The Abstract Map

Removing unnecessary detail to manage complexity, and packaging processes behind meaningful names.

Lesson Plan · Slides · Worksheet: Abstraction


Lesson 4 — Logic Gate Human Chain

Physically acting out AND, OR, and NOT gates to understand Boolean logic and compound conditions.

Lesson Plan · Slides · Resource: Gate Cards


Lesson 5 — The Logic Tournament

Applying Boolean reasoning strategically in a Guess Who-style game to evaluate question efficiency.

Lesson Plan · Slides · Worksheet: Strategy Analysis · Resource: Character Sheet


Lesson 6 — The Function Machine

Reverse-engineering reusable processes with inputs and outputs using a physical cardboard function machine.

Lesson Plan · Slides · Worksheet: Function Design · Resource: Input Slips


Year 9 — The Data Scientist

Students learn to think like a computer scientist, engaging with how data is represented and how algorithmic choices affect performance.

Theme: Representing information and making things fast.

Skills: Data Representation (Binary), Compression, Searching, Sorting, Graph Theory, Algorithmic Complexity.


Lesson 1 — The Human Fax Machine

Transmitting pixel images using binary and discovering compression through run-length encoding.

Lesson Plan · Slides · Worksheet: Compression · Resource: Pixel Images


Lesson 2 — The Number Hunt

Comparing linear and binary search strategies and graphing the dramatic difference in efficiency.

Lesson Plan · Slides · Worksheet: Results & Graph


Lesson 3 — The Sorting Race

Racing three teams using bubble sort, selection sort, and insertion sort to feel the impact of algorithm choice.

Lesson Plan · Slides · Worksheet: Tally Sheet · Resource: Algorithm Reference · Resource: Number Cards


Lesson 4 — The Sorting Network

Walking a physical parallel sorting network to experience how simultaneous operations differ from sequential processing.

Lesson Plan · Slides · Resource: Sorting Network Diagram · Resource: Number Cards


Lesson 5 — The Map Problem

Finding shortest paths and tackling the Travelling Salesman Problem to encounter graph theory and computational limits.

Lesson Plan · Slides · Worksheet: Route Finder · Resource: Island Map


Lesson 6 — The Complexity Olympics

A multi-station challenge demonstrating O(1), O(log n), O(n), and O(n²) growth rates through physical activities.

Lesson Plan · Slides · Worksheet: Results Recording · Resource: Station Cards


Copyright © Paul Baumgarten.