Angles and Turns
Year 6 students classify, estimate, and measure angles in degrees, and investigate angle relationships including angles on a straight line and in a triangle.
What You Need to Know
Key Concept Diagram
Angles are measured in degrees (°); a full turn is 360°
Acute angles are less than 90°; right angles equal 90°; obtuse angles are between 90° and 180°; reflex angles exceed 180°
Angles on a straight line always add to 180°
The three interior angles of any triangle always sum to 180°
Key Vocabulary
Acute angle
An angle measuring less than 90 degrees
Obtuse angle
An angle measuring between 90 and 180 degrees
Reflex angle
An angle measuring between 180 and 360 degrees
Protractor
A tool used to measure angles in degrees
Knowledge Check
Select the correct answer for each question. Click "Check Answer" to see if you are right.
Question 1
Two angles on a straight line measure 65° and x°. What is x?
Question 2
A triangle has angles of 40° and 75°. What is the third angle?
Question 3
Which type of angle measures 135°?
Key Concepts Summary
- ●Angles are measured in degrees (°); a full turn is 360°
- ●Acute angles are less than 90°; right angles equal 90°; obtuse angles are between 90° and 180°; reflex angles exceed 180°
- ●Angles on a straight line always add to 180°
- ●The three interior angles of any triangle always sum to 180°