Teaching and Group Activities for Understanding
Day 1 Teaching
Using an online protractor, show how to align the protractor to read the angle. Point out how the numbers of degrees go both anticlockwise and clockwise; this is the case on many protractors! Measure angles of 90°, 180°, 270°. Show different angles for children to estimate then measure.
Use the in-depth problem-solving investigation ‘Nine-pin triangles’ from NRICH as today’s group activity.
Or, use this activity:
-- Accurately draw and measure angles.
Day 2 Teaching
Introduce acute, obtuse and reflex angles.
Launch ‘Try it yourself’ from www.mathsisfun.com. Scroll down and move the top line of the angle anticlockwise to gradually increase it from 1° to 360°, asking children to watch the angle titles at the side. Draw some angles, and children classify them as acute, obtuse or reflex.
-- Classify angles as acute, obtuse or reflex through shape investigation.