Math lesson plan · 6th grade (Year 7 in England) · 45 minutes
Surface area using nets
Geometry
CCSS 6.G.A.4England: KS3 GeometryEngland: GCSE Foundation Geometry
Objective and success criteria
Students will: Surface area using nets.
- I can answer questions on today's skill on my own, without help.
- I can explain each step and say why it works.
- I can check my answer and spot a mistake.
Before and after
Needs first: Volume of cuboids (rectangular prisms); Area of triangles
Leads to: Surface area of cubes and cuboids; Surface area of triangular prisms
Materials: Rulers and protractors, Squared or dotted paper, Shape cut-outs, Mini whiteboards and pens, Printed student sheet (below).
Warm-up · 5 min
- Quick retrieval from earlier learning (Volume of cuboids (rectangular prisms); Area of triangles). Students answer on mini whiteboards.
- Show answers together and note who needs support in the main task.
- A box is 4 m long, 2 m wide and 6 m high. What is its volume, in m³? → 48Prompt: Volume = length × width × height.
- A box is 4 ft long, 3 ft wide and 7 ft high. What is its volume, in ft³? → 84Prompt: Volume = length × width × height.
- A box is 8 cm long, 7 cm wide and 2 cm high. What is its volume, in cm³? → 112Prompt: Volume = length × width × height.
Hook · 5 min
- Show a photo of a building, a tile pattern or a road sign and ask what shapes and angles students can spot.
- Share the objective: Surface area using nets. Read the success criteria together.
I do: model it · 10 min
- Work through the example out loud, saying why you do each step, not just what you do.
- Example: What is the surface area of a cuboid 3 yd × 4 yd × 5 yd, in yd²?
- Step 1: 3 × 4 = 12
- Step 2: 3 × 5 = 15
- Step 3: 4 × 5 = 20
- Step 4: 2 × (12 + 15 + 20) = 94 yd²
- Answer: 94
- Pause after each step and ask a student to say what comes next.
We do: guided practice · 10 min
- Do these together. Students try each step on whiteboards before you reveal it.
- Use the hints as prompts rather than giving the answer.
- What is the surface area of a cuboid 8 yd × 7 yd × 5 yd, in yd²? → 262Prompt: A cuboid has 6 faces in 3 matching pairs.
- A cube has edges of 12 cm. What is its total surface area, in cm²? → 864Prompt: A cube has 6 identical square faces.
You do: independent practice · 10 min
- Students work on the student sheet. Circulate and check the first two answers of every student early.
- Students who finish: write a question of their own for a partner, with the answer.
The 8 questions are on the student sheet below, with answers in the key.
Exit ticket · 5 min
- Two questions on their own. Sort answers into got it / nearly / not yet to plan the next lesson.
- A cube has edges of 7 m. What is its total surface area, in m²? → 294Prompt: A cube has 6 identical square faces.
- What is the surface area of a cuboid 5 ft × 4 ft × 8 ft, in ft²? → 184Prompt: A cuboid has 6 faces in 3 matching pairs.
Watch out for
- Thinking a square turned on its corner is no longer a square.
- Reading the wrong scale on a protractor.
Support and stretch
Support
- Review first: Volume of cuboids (rectangular prisms).
- Use concrete materials: rulers and protractors.
- Give the first step of each question, or a partly worked example to finish.
- Pair with a confident partner for the guided practice.
Stretch
- Move on to: Surface area of cubes and cuboids; Surface area of triangular prisms.
- Explain a common mistake in writing and how to fix it.
- Write a word problem that uses today's skill, then solve a partner's.
Homework and more practice
Free online practice with hints and printable worksheets for this skill: eurekami.com/math/grade-6.
Free lesson plan from eurekami.com/lesson-plan-builder