Computing · Year 3

Active learning ideas

Introducing Loops: Repeating Actions

Active learning works because loops become tangible when students physically repeat actions or see immediate visual results. Hands-on activities let students experience the efficiency of loops over manual repetition, building both understanding and confidence in programming concepts.

• National Curriculum Attainment Targets
• KS2: Computing - Programming
• KS2: Computing - Algorithms

• 20–40 min
• Pairs → Whole Class
• 4 activities

Activity 01

• Placemat Activity
• 20 min · Small Groups

Unplugged Demo: Human Loops

Students stand in a circle and perform actions like clapping or jumping. Teacher introduces a leader who says 'repeat 5 times: clap, jump'. Groups practise giving and following loop instructions, then discuss efficiency over manual repeats. Transition to block code examples on the board.

Explain the purpose of a loop in programming.

Facilitation Tip

During the Human Loops activity, position students in a circle to physically act out loop iterations so everyone sees how repetition is structured and controlled.

What to look for

Provide students with two code snippets: one drawing a square using four 'move' and four 'turn' blocks, and another using a 'repeat 4 times' loop with 'move' and 'turn' blocks inside. Ask: 'Which code is more efficient and why?'

• Understand
• Analyze
• Evaluate
• Self-Awareness
• Relationship Skills

Activity 02

• Placemat Activity
• 30 min · Pairs

Block Coding: Square Patterns

In Scratch or similar, students drag 'repeat 4' blocks around move and turn commands to draw squares. They test, adjust angles for perfect shapes, and add colours. Pairs challenge each other to create stars or houses with loops.

Compare using a loop to repeating the same block multiple times.

Facilitation Tip

After introducing block coding for squares, ask students to predict what happens if the repeat number changes before they run the program, reinforcing cause and effect.

What to look for

Display a simple repeating pattern on screen (e.g., a sprite drawing a triangle five times). Ask students to identify the action to be repeated and the number of times it needs to repeat to create the pattern.

• Understand
• Analyze
• Evaluate
• Self-Awareness
• Relationship Skills

Activity 03

• Placemat Activity
• 40 min · Small Groups

Loop Challenges Relay

Set up stations with task cards: repeat to draw circles, move in patterns, or animate sprites. Small groups complete one per station, passing iPads. Debrief as whole class on successes and loop benefits.

Construct a program that uses a loop to draw a repeating pattern.

Facilitation Tip

During Loop Challenges Relay, have teams swap completed challenges and peer-assess loop structures and outputs to build collaborative debugging skills.

What to look for

Pose the question: 'Imagine you need to make a sprite say 'Hello!' ten times. Would you drag out ten separate 'say' blocks, or use a loop? Explain your choice and how a loop makes programming easier.'

• Understand
• Analyze
• Evaluate
• Self-Awareness
• Relationship Skills

Activity 04

• Placemat Activity
• 25 min · Pairs

Debug and Remix

Provide starter programs with loop errors, like infinite repeats or misplaced blocks. Students fix in pairs, then remix a classmate's working program to add new looped actions. Share one remixed version with the class.

Explain the purpose of a loop in programming.

What to look for

Provide students with two code snippets: one drawing a square using four 'move' and four 'turn' blocks, and another using a 'repeat 4 times' loop with 'move' and 'turn' blocks inside. Ask: 'Which code is more efficient and why?'

• Understand
• Analyze
• Evaluate
• Self-Awareness
• Relationship Skills

A few notes on teaching this unit

Teach loops by starting with physical movement to connect abstraction to real-world actions. Avoid explaining loops theoretically; instead, let students discover their power through doing. Research shows that students grasp repetition best when they first experience it unplugged before moving to block coding, so build from concrete to abstract to support long-term retention.

Students will confidently use loops to repeat actions without error, explain why loops simplify code, and adjust loop counts to change program outcomes. They will compare looped and non-looped code to recognize efficiency and debugging advantages.

---

Watch Out for These Misconceptions

• During Human Loops, watch for students who act out loops indefinitely without stopping after the set count. Redirect by timing each iteration and stopping after the agreed repeat number.

  During Block Coding: Square Patterns, have students adjust the repeat number and observe the program end exactly at that count, proving loops stop when instructed. Encourage them to verbalize the stop condition to reinforce understanding.

• During Loop Challenges Relay, listen for students who assume loops can only repeat identical actions inside them. Redirect by asking teams to modify one action inside the loop to create variation.

  During Debug and Remix, guide students to identify that loops can contain different commands by analyzing how a loop with a 'move' and a 'change color' block creates a varied pattern. Discuss how this flexibility makes loops powerful.

• During Block Coding: Square Patterns, watch for students who manually repeat code instead of using loops despite instruction. Ask them to compare the length of their manual code with a peer’s looped version side by side.

  During Loop Challenges Relay, have students edit both manual and looped versions of a pattern to change the repeat count, highlighting the time and error savings loops provide when modifying programs.

---

Methods used in this brief

• Placemat Activity