Computing · Year 1

Active learning ideas

Finding and Fixing Errors (Debugging)

Active learning works well for debugging because Year 1 students need to see errors in action to understand them. Physical movement and hands-on tasks make invisible mistakes visible, turning abstract ideas into concrete problems they can solve together.

• National Curriculum Attainment Targets
• KS1: Computing - Algorithms
• KS1: Computing - Debugging

• 20–35 min
• Pairs → Whole Class
• 4 activities

Activity 01

• Plan-Do-Review
• 30 min · Pairs

Pairs Activity: Human Robot Debugging

One student acts as a 'robot' following partner's oral instructions to navigate a space with obstacles. Switch roles after observing errors like missed turns. Pairs discuss and revise instructions, then retest for success.

How do you know when something has gone wrong with a set of instructions?

Facilitation Tip

During Human Robot Debugging, stand slightly apart from students so they must listen carefully to your instructions without visual cues.

What to look for

Present students with a simple 3-step physical sequence (e.g., '1. Stand up. 2. Clap hands. 3. Sit down.'). Introduce one deliberate error (e.g., '1. Stand up. 2. Sit down. 3. Clap hands.'). Ask students to perform the sequence and then point to the step that caused the unexpected result.

• Remember
• Apply
• Analyze
• Self-Management
• Decision-Making
• Self-Awareness

Activity 02

• Plan-Do-Review
• 25 min · Small Groups

Small Groups: Sequence Card Sort

Provide cards showing a buggy sequence, such as building a tower with wrong block order. Groups identify the error through discussion, reorder cards, and test by stacking physically. Record before-and-after sequences on paper.

Can you spot what went wrong with these instructions?

Facilitation Tip

In Sequence Card Sort, arrange cards on a large table so students can see the whole sequence and discuss rearrangements as a group.

What to look for

Show students a visual representation of a buggy instruction set, like a set of arrows for drawing a shape that leads to the wrong shape. Ask: 'Which arrow is pointing the wrong way? How should we change it so it makes the correct shape?'

• Remember
• Apply
• Analyze
• Self-Management
• Decision-Making
• Self-Awareness

Activity 03

• Plan-Do-Review
• 35 min · Whole Class

Whole Class: Toy Path Challenge

Project a path for toy vehicles with deliberate errors like sharp turns. Class votes on problems, suggests fixes, and tests one at a time with the toy. Chart successful paths on the board.

What do you think will happen once we fix this mistake?

Facilitation Tip

For the Toy Path Challenge, use masking tape to mark paths on the floor so students can easily adjust routes and track corrections.

What to look for

Give each student a card with a simple 2-step instruction (e.g., '1. Pick up the red block. 2. Put it on the blue block.'). Then provide a 'buggy' version (e.g., '1. Pick up the blue block. 2. Put it on the red block.'). Ask students to write one sentence explaining what went wrong and one sentence explaining how to fix it.

• Remember
• Apply
• Analyze
• Self-Management
• Decision-Making
• Self-Awareness

Activity 04

• Plan-Do-Review
• 20 min · Individual

Individual: Personal Routine Fix

Students write or draw their morning routine with one planted error. Self-check by acting it out, note the issue, and rewrite correctly. Share one fix with the class.

How do you know when something has gone wrong with a set of instructions?

Facilitation Tip

During Personal Routine Fix, provide printed steps on separate sheets so students can physically rearrange or annotate the sequence.

What to look for

Present students with a simple 3-step physical sequence (e.g., '1. Stand up. 2. Clap hands. 3. Sit down.'). Introduce one deliberate error (e.g., '1. Stand up. 2. Sit down. 3. Clap hands.'). Ask students to perform the sequence and then point to the step that caused the unexpected result.

• Remember
• Apply
• Analyze
• Self-Management
• Decision-Making
• Self-Awareness

A few notes on teaching this unit

Teach debugging by making it social and iterative. Avoid rushing students to the 'right' answer, as this discourages exploration. Instead, model curiosity by asking open questions like 'What happens if we try this?' and normalise mistakes as part of learning. Research shows that peer discussion during debugging deepens understanding more than individual work.

Successful learning looks like students confidently identifying errors, explaining fixes clearly, and testing corrections until results match expectations. They should use precise language to describe what went wrong and how to correct it.

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Watch Out for These Misconceptions

• During Human Robot Debugging, students may assume the robot (partner) is not following instructions when actually the instructions contain errors.

  Listen for students blaming their partner and redirect them to re-read the steps aloud together, pointing to each instruction as they perform it.

• During Sequence Card Sort, students may believe the sequence is correct if it looks orderly, even if the order is wrong.

  Ask students to physically act out the card order to see where the flow breaks, then discuss why the visual order can be misleading.

• During Toy Path Challenge, students may think the toy’s path is correct if the toy moves, even if it doesn’t reach the target.

  Have students mark the toy’s actual path with chalk or tape, then compare it to the intended path to identify where the instructions failed.

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Methods used in this brief

• Plan-Do-Review