Year level: 4

Strand: Measurement

Lesson length: 60 mins

In this second of two lessons, students create their own chalk designs in the style of a stained-glass window that includes different types of angles.

In a previous lesson, Angles: types of angles, students explored ways to compare angles and recognise the names of the different angles, including right angles, acute angles, obtuse angles, straight angles, reflex angles and revolutions.

### Achievement standard

By the end of Year 4, students compare angles relative to a right angle using angle names.

### Content descriptions

Students estimate and compare angles using angle names including acute angle, obtuse angle, straight angle, reflex angle and revolution, and recognise their relationship to a right angle. AC9M4M04

### General capabilities

Numeracy

• Understanding geometric properties Level 4

Critical and Creative Thinking | Inquiring

• Identify, process and evaluate information Level 3

Digital literacy

• Use observation and informal conversations to access students’ proficiency in identifying, describing and representing right angles, acute angles, obtuse angles, straight angles, reflex angles and revolutions

Some students may:

• have relatively limited experience with angles, how angles are measured, the names of different angles and their relationship to right angles
• not yet be familiar with the idea that angles are measures of turn and that we can estimate the size of angles using a right angle as a starting point or benchmark
• be unfamiliar with the names of the different angles, so it will be important to create a visual chart to help them to become more familiar with the names of the different angles and how the size of each angle can be compared to a right angle.

Prior to this lesson, it is assumed that students have knowledge of:

• angles as measures of turn
• how to compare angles to right angles (greater than or less than) in everyday situations
• how to identify patterns of geometric shapes in the environment.

## What you need:

• Lesson plan (Word)

• Teacher’s slides (PowerPoint)

• Angle checker made by each student in previous lesson

• Masking tape, coloured chalk and a safe marked-off area of concrete or asphalt within the school grounds within which to create their designs