Prototype Testing Sprint

Overview

Students refine a chosen LEGO STEM Prime design, test it against simple design criteria, and improve it using a design thinking cycle (empathise/define, ideate, prototype, test, refine). This builds on earlier idea generation and model-making by focusing on safe, methodical refinement and evaluation.

Learning intentions

• Students will identify a design problem and state clear success criteria for a working LEGO model.
• Students will follow a sequence of steps to build and modify a prototype safely and accurately.
• Students will test their solution fairly, record observations, and explain what changes will improve performance.
• Students will communicate design decisions using labelled diagrams and technical language.

Success criteria

• I can describe the user need and the design criteria in my own words.
• I can test my prototype using a consistent method and record results.
• I can refine my model based on evidence from testing (not just “it looks better”).
• I can explain my changes using clear technical terms and an annotated diagram.

Curriculum links

• Design and Technologies — generate, communicate and evaluate design ideas, and use materials, equipment and steps to safely make a solution for a purpose.
• Design and Technologies — sequence steps to individually and collaboratively make designed solutions (plan, build, then test and refine).
• Design and Technologies — generate and communicate design ideas and decisions using appropriate attributions, technical terms and graphical representation techniques, including using digital tools (optional documentation).
• Digital Technologies (integrated) — implement simple algorithms as visual programs involving control structures and input (use an unplugged “rule set” to guide testing or refinement, if the kit activity supports it).

Lesson structure (60 minutes)

1. 0–6 min · Hook: What makes a better prototype? Teacher demonstrates two quick “prototype” versions (fast sketch or 30-second video/photo) and asks: “Which one works better and why?” Students discuss in pairs and share one evidence-based reason.

2. 6–12 min · Define criteria & safety check Teacher revisits the design brief from the previous lesson and posts 3–4 class-agreed success criteria (e.g., stability, speed, accuracy, strength, correct function). Students select their own target criteria and rewrite them in a personal checklist; teacher leads a brief Safety by Design reminder (handling small parts, tool use, testing area boundaries).

3. 12–22 min · Prototype build (refinement focus) Teacher models the refinement mindset: “Keep what works, change one thing at a time.” Students build or adjust their LEGO STEM Prime prototype using provided steps. Teacher circulates to check safe equipment use and that changes match the chosen criteria.

4. 22–35 min · Testing (fair, consistent, recorded) Teacher explains the test method: same start point, same run time/turns/trials, same measurement tool (stopwatch/counts/rubric). Students test their prototype for 3 trials, recording results in a simple table (Trial 1–3, what happened, score/notes). Students also note one “unexpected observation” for gifted stretch thinking.

5. 35–46 min · Evidence-based refinement Teacher provides sentence starters: “My prototype failed the criterion because…”, “I will change… to improve…”, “After changing, I predict…”. Students choose one modification supported by their evidence and update their model. Where helpful, students produce a quick labelled sketch showing the changed part and intended effect.

6. 46–55 min · Retest & evaluate Teacher runs a retest round with the same method. Students retest (at least 1–2 trials) and compare to earlier results. Students complete a fast evaluation using a 3-point scale per criterion (Met / Almost / Not yet) and a short explanation.

7. 55–60 min · Exit reflection: One improvement, one question Students write one “next step” refinement and one question they would investigate if they had more time (e.g., “What if we change the gear ratio?” “How does stability change with a different base?”). Teacher collects for formative assessment.

Resources

• LEGO STEM Prime kits (one per group or per student, depending on class setup)
• Prototype planning sheet (criteria checklist + results table)
• Paper clipboards or data recording sheets
• Stopwatch/phone timers
• Measurement aids (ruler/tape measure, markers, scoring cards)
• Safety reminder cards for small parts and tool use
• Coloured pencils for labelled diagrams
• Optional: simple digital documentation template (only if devices are available and approved)

Assessment

• Formative during build: teacher checks students are refining with a clear link to criteria (listen for “because my test showed…”).
• Formative during testing: review recording tables for accuracy and consistency of method across trials.
• Formative during evaluation: check annotated sketch clarity and technical wording (e.g., frame/base, axle/gear, support/bracing, connector type).
• Exit ticket: “next step + question” to gauge evidence-based reasoning and readiness for further iteration.

Differentiation

• Support: provide a single-page test procedure and sentence starters; offer a “change one variable” prompt; allow a partner to hold the timer so each student can focus on observations.
• Scaffolding for gifted learners: require an evidence claim using data (e.g., “Trial scores improved from __ to __ after changing __”).
• EAL/SEN: allow verbal recording of results to an adult or peer, then transcribe; use simplified diagrams with labelled part names from a class word bank.
• Extension-ready grouping: assign one “criteria captain” student to ensure the group tests fairly and documents consistently.

Extension (for advanced learners)

• Predict–test–justify: before the retest, students write a prediction tied to a specific mechanism change (e.g., “Changing the axle position will increase torque” or “Adding bracing will reduce wobble”), then must justify with evidence after testing.
• Optimisation challenge: improve one additional criterion without breaking the original (e.g., faster but still stable). Students document the trade-off using a two-column table: “Improved” vs “Trade-off / risk”.
• Algorithm link: create a simple “if/then” rule set to guide testing decisions (e.g., “IF the prototype fails trial 1, THEN run trial 2 after adjusting alignment”) and explain how it affects results, using plain language or visual steps.