Lesson 7: Waka Design Challenge — Capstone | Wero Hoahoa Waka
Summative project: Students act as waka engineers, designing an optimised hull that integrates all unit concepts — Newton's three laws, momentum, friction, buoyancy, and drag — in an authentic Māori-Pacific engineering brief. Optional: build and test a scale model.
📎 Learning Intentions
Know | Mōhio
- That waka hourua design represents sophisticated applied physics — buoyancy (Archimedes' principle), drag minimization, thrust optimisation, and stability are all engineering challenges.
- That physics knowledge is cumulative — each law from this unit applies simultaneously in the finished waka system.
- That the Engineering Design Process (Define → Research → Ideate → Prototype → Test → Improve) is how professional engineers — including Māori master builders (tohunga tārai waka) — work.
Demonstrate | Whakaatu
- Produce a complete Waka Design Report applying at least 4 physics principles from this unit with correct equations and justifications.
- Calculate: buoyancy force (Archimedes), expected drag (qualitative), estimated thrust-to-drag ratio, and momentum at cruising speed.
- Write a 1-page kaitiakitanga statement: how the design respects the materials and the ocean environment.
📐 Curriculum Alignment
Students will understand the nature of science as a human endeavour, appreciate its history and the way it develops, and recognise its relationship with technology.Ministry of Education (2007). The New Zealand Curriculum, p. 17.
Students will take increasing responsibility for their own learning and will reflect on and evaluate their own processes and outcomes.Ministry of Education (2007). The New Zealand Curriculum, p. 34.
🌿 Whakatūwhera — Opening
Tohunga tārai waka — ko ia te kaitiaki o ngā ara moana.
"The master waka carver — they are the guardian of the ocean pathways." A tohunga tārai waka spent years learning which timber has the right density, which hull shape resists tipping in swells, how to balance hull weight against buoyancy. They were physicists without the terminology — their knowledge was embodied, tested, and refined across generations. Today you join that tradition.
🎤 Kaiako Hook (5 min)
Show images and video of the Te Aurere waka hourua (traditional voyaging canoe) and the Emirates Team New Zealand AC75 side by side. Ask: "What physics challenges did both design teams face? What is similar? What is radically different?"
📚 Capstone Design Brief
The Design Challenge
🛶 Engineering Brief: Waka Hourua Optimisation
You are a tohunga tārai waka designing a modern waka hourua for inter-island racing between Aotearoa and Rarotonga. Your brief:
- Mass optimisation: The waka must float (buoyancy ≥ weight). Total mass target: 3,500 kg. Water density: 1,025 kg/m³. Calculate minimum hull volume needed for neutral buoyancy.
- Thrust analysis: Your wingsail generates 25,000 N of thrust. What drag force must the hull produce ≤ 25,000 N to allow acceleration? What design features achieve this?
- Momentum at cruising speed: At 12 m/s, calculate the waka's momentum. If it needs to stop within 100 m (emergency), what average braking force is needed?
- Newton's Laws Application: Using all three laws, describe what happens when: (a) the crew trims the sails to increase thrust, (b) the waka hits a crossing swell, (c) crew weight shifts to the windward hull.
- Kaitiakitanga Statement: Which materials do you choose and why? What is your plan for the waka's eventual retirement (it will not be sent to landfill)?
Assessment Rubric
| Criterion | Achieved (4–5) | Merit (6–7) | Excellence (8) |
|---|---|---|---|
| Physics Application | Applies 2–3 laws with basic equations | Applies all 4 laws with correct calculations | Integrates laws across scenarios; identifies force interactions between principles |
| Calculations | Mostly correct with minor arithmetic errors | All calculations correct with units shown | All calculations correct; discusses sources of experimental error and real-world complicating factors |
| Waka Design Logic | Design choices stated | Design choices justified with physics reasoning | Design optimisations compared; trade-offs explicitly acknowledged |
| Kaitiakitanga | Statement mentions environment | Connects material choices to environmental impact with evidence | Full lifecycle analysis; connects to traditional tohunga tārai waka practices |
Optional: Prototype Build & Test
If time and resources allow, students build a scale waka model (foil trays, clay, straws) and test it in the school pool or a large basin. Measure: Does it float? Speed over 2 m? Stability under simulated swell (gentle wave)? Compare observed results to theoretical predictions.
If 3D printing is available: students can design hulls in TinkerCAD and print them for water testing — a direct link to the design technology strand.
Gallery and Peer Review (30 min)
Designs are displayed for a gallery walk. Peers use a structured feedback protocol:
- One physics strength: "This design correctly applies ___ because ___."
- One question: "I wonder if ___ would improve ___ because ___."
- One kaitiakitanga connection: "This design respects the environment by ___."
✅ Unit Completion Checklist
🧑🏫 By Unit's End, Every Student Should:
- ☐ Identify and classify contact and non-contact forces; draw free body diagrams.
- ☐ State and apply Newton's First Law (inertia) to real scenarios.
- ☐ Use F = ma to solve for force, mass, or acceleration.
- ☐ Identify action-reaction force pairs (Newton's Third Law).
- ☐ Calculate momentum (p = mv) and verify conservation in collisions.
- ☐ Measure friction coefficients; explain drag and terminal velocity.
- ☐ Integrate at least two physics principles in a design analysis.
- ☐ Connect physics concepts to Māori and Pacific cultural contexts with genuine understanding.