Build a Windmill That Works

Overview

Lesson 3 of 4 in Harnessing Wind: Malawi in Miniature. Students construct a free-standing windmill tower from accessible materials, attach balanced blades, and improve their design through testing, peer feedback and reflection. The lesson connects making in Visual Arts with purposeful technological practice.

Learning intentions

• WALT construct a strong, free-standing windmill tower.
• WALT join and reinforce materials safely and effectively.
• WALT attach balanced blades to an axle so they rotate in moving air.
• WALT test, discuss and improve a design through trial and error.
• WALT show Niwha by persisting when a design does not work immediately.

Success criteria

• I can build a tower that stands upright independently.
• I can join and reinforce materials safely.
• I can attach blades to an axle.
• I can make blades that spin when gently blown on and explain one improvement I made.

Curriculum links

• Technology: Technological Practice — students identify a practical need, develop and test ideas, and evaluate how well their design works.
• Technology: Technological Products — students select and manipulate materials to make a functional product.
• Visual Arts: Practical Knowledge — students explore properties of materials, construction methods, structure, balance and movement.
• Key Competencies and class values — thinking, managing self, participating and contributing, alongside Manaaki, Aroha, Niwha and Atamai.

Lesson structure (60 minutes)

1. 0–7 minutes – Hook and design challenge Open with the windmill challenge introduction. Show a striking image of a simple windmill in Malawi and ask: “What must be true for a windmill to stay standing and still turn?” Briefly revisit the previous lesson’s ideas about wind, purpose and visual design. Share the WALT and success criteria.

2. 7–15 minutes – Demonstrate safe construction Use the construction and safety slides while demonstrating a tower, axle and blade system. Model a wide base, triangular bracing, tight joins, a straight axle and evenly spaced blades. Explicitly teach safe hot-glue routines: only the teacher or an adult supervises the hot-glue station; students wait with materials prepared and never touch glue or the metal nozzle.

3. 15–32 minutes – Build the tower Distribute the windmill build and test record and explain that students will sketch, record changes and note test results. In pairs or small groups, students use ice-block sticks and cardboard to build a tower that stands independently. Provide pre-measured components where needed. Circulate with prompts: “Where is the weight?” “Which join is weakest?” and “How could a brace make this stronger?” Students use hot glue only at the supervised station, or choose tape, split pins or wire.

4. 32–42 minutes – Add axle and blades Students attach an axle and cardboard blades, aiming for even spacing and similar blade sizes. Test each windmill with a gentle breath or hand fan. Encourage students to alter one variable at a time, such as blade angle, number, size or axle tightness, and record the change on the windmill build and test record.

5. 42–49 minutes – Peer feedback pause Open the peer-feedback prompts and organise a quick gallery test. Each group visits another windmill and gives two specific comments: one strength about stability or rotation, and one suggested improvement. Students use respectful language that demonstrates Manaaki and Aroha. The builder listens, asks one clarifying question and chooses one improvement to try.

6. 49–56 minutes – Improve and retest Groups strengthen a join, adjust the axle, rebalance blades or change their blade design. They retest using the same gentle air source and record whether rotation improved. Invite groups to explain how their evidence led to the change, rather than simply saying that the new design “looks better”.

7. 56–60 minutes – Share and reflect Use the plenary and reflection slides. Each group briefly demonstrates its windmill and completes the sentence: “Our windmill works because…” or “Our next improvement would be…”. Collect the windmill build and test record to assess construction decisions, testing and reflection. Preview the final lesson, where students will refine presentation and share the completed Malawi-inspired miniature.

Resources

• the windmill challenge and construction slide deck
• the windmill build and test record
• Ice-block sticks, cardboard and recycled card
• Axles such as wooden skewers, dowel or straight wire
• Cardboard blade templates or scissors for designing blades
• Hot-glue gun and glue sticks, used only at an adult-supervised station
• Masking tape, split pins and craft wire as alternative joining materials
• Hand fans or folded card for testing airflow
• Rulers, pencils, scissors and markers
• Safety glasses and a clear testing area

Assessment

• Observe whether each tower stands independently, has reinforced joins and shows safe material use.
• Check the windmill during testing: blades are attached to the axle and rotate when gently blown on.
• Use the build-and-test record and peer feedback to assess students’ ability to identify a problem, make an informed change and explain the result.

Differentiation

• Provide a simple tower diagram, a partly assembled example, pre-measured components and a short visual sequence of construction steps.
• Use mixed-ability peer builders, assigning roles such as materials manager, builder, tester and recorder so every student contributes.
• Offer adult-supervised hot-glue support and alternatives including tape, split pins or wire. Allow students to demonstrate explanations orally, visually or in writing.
• Extend confident learners by asking them to investigate blade number, angle, size or axle friction. They should change one variable, complete repeated tests and record results in a table.