### Teaching and Group Activities for Understanding

**Day 1 Teaching**

Introduce the terminology for circles: radius, diameter, and circumference. Show children a compass and model how to use it to draw a circle. Discuss drawing circles with specified radii. Observe that the diameter is double the radius.**Group Activities**

-- Use compasses to draw circles with measured radii.

**Day 2 Teaching**

Show a large 50p coin and agree (having noted slightly curved sides and rounded corners) that it is a heptagon. Children draw irregular heptagons. Identify types of angle within it. Explain that all polygons have straight sides and are closed. Discuss what makes a good description of a polygon.

**Group Activities**

-- Identify the properties of polygons and use this to sort them.

-- Draw 2-D shapes based on given properties.

**Day 3 Teaching**

Show children five different triangles and discuss their similarities and differences. Look at the number of sides and angles, lines of symmetry, length of sides, sizes of angles. Name the triangles as: equilateral, isosceles, right angled, scalene. Note that a right angled triangle can also be isosceles. Sort triangles according to different properties, e.g. has a right angle or not.**Group Activities**

Use the in-depth problem-solving investigation ‘Egyptian Rope’ from NRICH as today’s group activity.

Or, use this activity:

-- Identify right angles and other properties in triangles; classify them.