Outstanding Computing Interview Lesson – Algorithms (KS2) | Jam Sandwich Bot Activity

Engaging 20–45 minute lesson ideal for observations, interviews, or Ofsted

This practical and well-structured KS2 computing lesson helps children understand what algorithms are and how to debug them, using the ever-popular Jam Sandwich Bot activity. Originally created by an experienced computing lead for an interview lesson, it’s now a go-to favourite for anyone wanting to teach algorithms in a memorable, hands-on way.

What’s the lesson about?
Children explore how to write and debug simple algorithms by “programming” the teacher to make a jam sandwich. This encourages precise instructions, teamwork, and plenty of laughter—all while covering key computing objectives.

What’s included:
★ A detailed lesson plan with clear structure and timing suggestions
★ PowerPoint presentation to guide the lesson and explain new vocabulary
★ Debugging worksheet for independent or paired work
★ Printable keyword posters with clear definitions for display or recap

How to use it:

• Start with the PowerPoint to introduce key terms
• Use the Jam Sandwich Bot activity to demonstrate the need for clear, logical instructions
• Follow up with the debugging worksheet to reinforce the learning
• Display the keyword posters to keep computing language visible throughout the topic

Why it works well:
✔ Simple to deliver with clear guidance and resources
✔ Highly engaging and interactive
✔ Encourages problem solving and logical thinking
✔ Easy to adapt for different timings or ability levels
✔ Ideal for Year 3 and Year 4, but adaptable across KS2

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Stand out in interviews or observations by bringing a unique and exciting lesson to the table. Make computing memorable with the Jam Sandwich Bot!

Tags: KS2 computing | algorithms | debugging | jam sandwich activity | computing interview lesson | Year 3 | Year 4 | observation lesson | Ofsted | programming | logical thinking | lesson plan | classroom resources