Mathematics

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50 mins

Teacher/Student led

Learning Goals

Learning Outcomes

Lesson Files

+80 XP

Teacher-led from the board. Pupils do not need a device, but can follow on one.

What you need:
IWB/Projector/Large Screen
Protractor

Angles on a Line, at a Point and Vertically Opposite

Learn three essential angle facts: angles on a straight line sum to 180°, angles around a point sum to 360°, and vertically opposite angles are equal. Practise spotting which fact applies and calculating missing angles.

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1 Getting Started
2 Watch and Notice
3 Try It Together
4 Sketch and Solve in Your Copy
5 Class Challenge
6 What Did We Notice?
7 What's Next
Pupil practice

Your turn

Your teacher is running this lesson on the board. Here is the part you can try yourself.

Your written work is on page 74

Angle tool

1 - Getting Started ~4 mins

Illustration for Getting Started Look at the board: two straight roads cross each other, and one of the four angles is marked 70°.

What can we say about the other three angles just by looking? Which ones do you think are also 70°, and which are different?

👇 Mark your steps as done as you complete them.

+5 XP

2 - Watch and Notice ~10 mins

Three angle facts come up on screen, one at a time: angles on a straight line, angles round a point, and two lines crossing. Watch what stays the same each time and work out each missing angle from the fact shown.

👇 Mark your steps as done as you complete them.

+10 XP

3 - Try It Together ~10 mins

What to do

Today we work these out together on the board. Predict each missing angle before we check it.

A line: one angle is 140°. Find the other.
A point: 90°, 150° and one unknown. Find the unknown.
A crossing: one angle is 55°. Name all four angles.

Find the missing angle

+15 XP

4 - Sketch and Solve in Your Copy ~6 mins

COPYBOOK MOMENT

In your maths copy, sketch the three diagrams you just worked (line, point and cross). Under each one, write the calculation that finds the missing angle, for example 180° − 140° = 40°. Ring your answer.

+10 XP

Pupil practice

Module 7 · 2D Shape, 3D Shape and Angles Shape & Space

Lesson 80 · Angles on a Line, at a Point and Vertically Opposite

Download Activity Book page (PDF)

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