Teacher guide · Think Lab · Harder · about 35 min

📐 Angles Explorer

Pupils practise problem solving through "Angles Explorer": Acute, obtuse, right and reflex.

Lesson guide

  1. 1. Hook · 5 min

    Show the 📐 mission title and read the opening: "An angle of 90° is called…". Take three quick guesses.

  2. 2. Model · 5 min

    Think aloud through the first step together. Use Cog the Owl's line as your prompt: "Good thinking. Show me the why."

  3. 3. Do · 10 min

    Pairs work through the 5 steps on screen or on the printed sheet. Circulate and ask "why?"

  4. 4. Discuss · 10 min

    Use two or three of the discussion questions. Ask pairs to share different answers, not just correct ones.

  5. 5. Reflect · 5 min

    Exit ticket: one sentence on how they used problem solving today.

Discussion questions

  • What was the hardest choice in "Angles Explorer", and why?
  • An angle of 90° is called… — explain your reasoning to a partner.
  • Angles in a triangle add up to… — explain your reasoning to a partner.
  • Two angles of a triangle are 50° and 60°. The third is… — explain your reasoning to a partner.
  • Where could you use problem solving outside school this week?
  • If you did this again, what would you change?

Adapting it

Support: Read prompts aloud, pair with a confident partner, and accept spoken or drawn answers for writing steps.

Stretch: Ask pupils to create their own extra step for a partner and explain the correct answer.

Curriculum links

  • National Curriculum: Maths: number, calculation, fractions and reasoning (KS1/KS2)
  • National Curriculum: Maths: reasoning mathematically and problem solving
  • National Curriculum: Computing: logical reasoning and algorithms
  • PSHE: Living in the wider world: making decisions and evaluating choices

Pupil sheet

📐 Angles Explorer

Name: ____________________   Date: __________

  1. 1. An angle of 90° is called…

    ☐ A right angle

    ☐ Acute

    ☐ Obtuse

  2. 2. Angles in a triangle add up to…

    ☐ 180°

    ☐ 360°

    ☐ 90°

  3. 3. Match the angle to its name.

    45° → ________________

    120° → ________________

    90° → ________________

    270° → ________________

  4. 4. Two angles of a triangle are 50° and 60°. The third is…

    ☐ 70°

    ☐ 80°

    ☐ 90°

  5. 5. Find 3 right angles in your room and describe them.