Algorithmic Thinking

Active learning works for algorithmic thinking because students must experience the gap between vague instructions and precise steps themselves. When they try to follow or debug instructions in real time, they quickly see why clarity and order matter. These moments of frustration turn into lasting understanding of how algorithms function in everyday tasks.

• Year 6
• Technologies
• 4 activities
• 25 min–45 min

Learning Objectives

1. Design an algorithm to sort a list of numbers from smallest to largest.
2. Compare two different algorithms for the same task, evaluating their efficiency.
3. Explain why precise, unambiguous steps are crucial for an algorithm to function correctly.
4. Deconstruct a simple real-world task into a sequence of logical steps.

Problem-Based Learning

⏱ 30 min·Pairs

Pairs: Direction Following Challenge

Pairs take turns giving verbal algorithms for a partner to draw simple shapes blindfolded, like a house or robot. Switch roles after 5 minutes, then discuss unclear steps. Refine algorithms based on feedback.

Prepare & details

Explain the importance of clear and precise steps in an algorithm.

Facilitation Tip: During the Direction Following Challenge, circulate and listen for students using vague words like “around” or “close to” that will confuse their partners.

Setup: Groups at tables with access to research materials

Materials: Problem scenario document, KWL chart or inquiry framework, Resource library, Solution presentation template

• Analyze
• Evaluate
• Create
• Decision-Making
• Self-Management
• Relationship Skills

Problem-Based Learning

⏱ 45 min·Small Groups

Small Groups: Sorting Algorithm Race

Provide groups with 20 mixed animal cards. Design and test two algorithms to sort by size: one sequential check, one pairwise swap. Time each, compare efficiency, and share winners.

Prepare & details

Compare different algorithms for solving the same problem in terms of efficiency.

Facilitation Tip: During the Sorting Algorithm Race, time each group and post results publicly to emphasize that efficiency is measurable and objective.

Setup: Groups at tables with access to research materials

Materials: Problem scenario document, KWL chart or inquiry framework, Resource library, Solution presentation template

• Analyze
• Evaluate
• Create
• Decision-Making
• Self-Management
• Relationship Skills

Problem-Based Learning

⏱ 35 min·Whole Class

Whole Class: Human Algorithm Demo

Select student 'executors' to follow a class-devised algorithm for a task like packing a lunchbox. Class observes errors, votes on fixes, and iterates twice for precision.

Prepare & details

Design an algorithm to sort a list of items in a specific order.

Facilitation Tip: During the Human Algorithm Demo, pause after each step to ask students what would happen if a step were missing or out of order.

Setup: Groups at tables with access to research materials

Materials: Problem scenario document, KWL chart or inquiry framework, Resource library, Solution presentation template

• Analyze
• Evaluate
• Create
• Decision-Making
• Self-Management
• Relationship Skills

Problem-Based Learning

⏱ 25 min·Individual

Individual: Algorithm Flowchart

Students draw flowcharts for sorting laundry by color. Test by tracing with sample inputs, predict outputs, and note improvements for efficiency.

Prepare & details

Explain the importance of clear and precise steps in an algorithm.

Facilitation Tip: For the Algorithm Flowchart, remind students to use shapes for clarity, such as rectangles for actions and diamonds for decisions.

Setup: Groups at tables with access to research materials

Materials: Problem scenario document, KWL chart or inquiry framework, Resource library, Solution presentation template

• Analyze
• Evaluate
• Create
• Decision-Making
• Self-Management
• Relationship Skills

Teaching This Topic

Teach algorithmic thinking by making the invisible visible. Have students act out algorithms first before writing them down, so they connect process to product. Avoid rushing to code or digital tools; unplugged activities build foundational clarity. Research shows that students who test their own algorithms with peers develop stronger debugging habits and deeper conceptual understanding.

What to Expect

Successful learning looks like students writing clear, testable algorithms that peers can follow without confusion. They should compare algorithms by speed and accuracy, and adjust their own work based on feedback. Clear explanations and logical flow in their designs show they grasp the core idea.

Watch Out for These Misconceptions

Common Misconception

During the Direction Following Challenge, watch for students assuming their instructions are clear until a peer tries to follow them literally.

What to Teach Instead

After the Direction Following Challenge, ask each pair to share one instruction that caused confusion. Discuss how replacing vague terms with exact measurements or directions improves clarity.

Common Misconception

During the Sorting Algorithm Race, watch for students believing a longer list of steps always means a slower algorithm.

What to Teach Instead

During the Sorting Algorithm Race, have groups compare their timed results with a second group using a shorter but more repetitive algorithm. Use the data to show that logic, not length, determines efficiency.

Common Misconception

During the Human Algorithm Demo, watch for students linking algorithms only to computers or coding.

What to Teach Instead

After the Human Algorithm Demo, ask students to name one non-digital system (e.g., baking a cake) that uses algorithms and explain how the steps follow the same principles as their demos.

Assessment Ideas

Quick Check

After the Direction Following Challenge, collect students’ written algorithms and look for missing or ambiguous steps. Ask one student to read an algorithm aloud while another follows it step by step to reveal gaps.

Peer Assessment

During the Sorting Algorithm Race, have students swap algorithms with another group and time how long it takes to execute both. Each group provides written feedback on clarity and efficiency before sharing results publicly.

Exit Ticket

After the Algorithm Flowchart activity, give students two flowcharts for sorting the same list. They write one sentence comparing the two and circle the one they think is more efficient, justifying their choice with evidence from their work.

Extensions & Scaffolding

• Challenge: Ask students to write an algorithm for tying a shoe, then refine it by removing redundant steps while keeping it foolproof.
• Scaffolding: Provide partially completed algorithms with missing steps for students to fill in during the Direction Following Challenge.
• Deeper exploration: Introduce conditional steps (e.g., “if the list is empty, stop”) and have students modify their sorting algorithms to handle edge cases.

Key Vocabulary

Algorithm	A set of step-by-step instructions or rules designed to solve a problem or complete a task.
Sequence	The order in which instructions are performed. Changing the sequence can change the outcome of an algorithm.
Efficiency	How quickly or with how few steps an algorithm can complete its task. A more efficient algorithm uses fewer resources.
Debugging	The process of finding and fixing errors or problems within an algorithm or computer program.