Cardboard Structures

Overview

This lesson introduces a simple design challenge using cardboard. Students test ideas, build a stable structure, and explain how cardboard properties help their design. This builds on earlier learning in the unit “Design, Make, Innovate: Year 3” by moving from exploring materials to applying them in a purposeful build.

Learning intentions

WALT create a simple structure using cardboard. WALT use a repeatable plan to test and improve how our structure stands. WALT compare and describe how cardboard behaves (for example, bending, holding shape, and strength).

Success criteria

I can plan my structure with clear steps (measure/cut and join). I can build a cardboard structure that stands on its own. I can explain one improvement I made after testing. I can use safe practices when cutting, bending, and joining cardboard.

Curriculum links

• Technology (Design and develop): Students create and adapt ideas, using materials and simple tools to meet a need or problem.
• Technology (Communicating ideas): Students describe their design processes and give reasons for choices.
• Science link (Material properties and uses): Students apply knowledge of how common materials behave and use simple comparisons to guide use (including elastic behaviour when stretched/compressed, if used as a small “string/tape band” component).
• Key competencies: Thinking (trial, improve, explain), Using language symbols and texts (draw/label steps), Managing self (safe tool use), Participating and contributing (group roles and sharing tests).

Lesson structure (30 minutes)

1. 0–3 min · Hook (demo + question). Teacher shows two quick cardboard shapes (one flat-only, one with a fold/triangle support) and asks: “Which will stand better and why?” Students turn-and-talk, then share one idea.

2. 3–8 min · Mini-teach (cardboard properties for design). Teacher displays a visual slide with 3 “cardboard helps” statements:

• “Cardboard can bend (especially along folds).”
• “Cardboard can hold shape when folded into braces.”
• “Cardboard is easiest to join with tape/glue that stays strong.” Teacher also reminds: “Triangles and folds often make stronger shapes.” Students repeat the statements and point to an example.

3. 8–13 min · Understand the challenge (design brief + roles). Teacher explains the challenge: “Build a cardboard structure that stands upright and supports a small weight (paper cup or eraser) for 10 seconds.” Constraints (simple and visible):

• Use only provided cardboard pieces, tape, and glue sticks (or plastic-safe tape).
• Structure must be freestanding (no hands holding during the test).
• Time limit: 8 minutes building, 2 minutes testing/improving. Group roles: Builder, Cutter (or “score-and-snap” helper), Tester, Safety Officer. Students select roles and read the success criteria.

4. 13–16 min · Plan (quick sketch + steps). Teacher models a 3-step plan on the board: Draw → Cut/score → Join → Test. Students do a quick sketch in their booklet: shape + where folds/triangles will be.

5. 16–24 min · Make + test (cycle 1). Teacher circulates with a check: “What will you try first? How will you make it stand?” and supports safety. Students build, then test once at the end of cycle 1 (structure stands? weight holds 10 seconds?).

6. 24–28 min · Improve (cycle 2). Teacher prompts: “Choose one change: add a fold/bracing, strengthen a join, or change the base.” Students revise and test again.

7. 28–30 min · Share + reflect (closing statements). Teacher asks: “What cardboard property helped your design? What improvement worked best?” Students share in pairs, then one group shares with the class.

Resources

• Assorted cardboard sheets/boxes (pre-cut into manageable sizes where possible)
• Scissors and child-safe craft knives (teacher-controlled) or score-and-snap tools
• Rulers, pencils, and simple measuring cards
• Tape (masking or clear), glue sticks (and optional low-mess glue if available)
• Paper cups/erasers as small weights
• Safety signs/laminated tool reminders
• Student design booklet or half-page template (sketch + steps + “tested/improved” box)
• Timer for test: “10 seconds”
• Whiteboard/slide deck with large-font visuals

Assessment

• During making: observe group plans and whether students can articulate a choice (fold, brace, join).
• During testing: note if students use a clear improvement after feedback (not random rebuilding).
• Quick teacher checklist (per group): plan drawn, structure freestanding, test completed, explanation includes a reason.

Differentiation

• Support for lower Year 2 students:
• Provide a “starter template” showing a triangle brace and a fold line option.
• Offer sentence starters: “I chose cardboard because…”, “I improved it by…”, “It worked better because…”
• Pre-assign roles and give a guided cut list (pre-marked fold lines).
• Stretch for higher Year 3 students:
• Add a second target: “Make it stand on a smaller base” or “Add one additional support without adding more pieces.”
• Challenge explanation quality: “Which join method is strongest and why?”
• Mixed-group management:
• Keep a visible build checklist on the slide so both year groups follow the same steps.
• Ensure Tester and Safety Officer roles rotate so everyone participates.
• EAL/SEN considerations:
• Use images for steps and allow gestures/pointing to show explanations.
• Keep instructions short and repeat key constraints at the start of making.