### Teaching and Group Activities for Understanding

**Day 1 Teaching**

Pairs discuss how to explain the radius, circumference and diameter to someone with no diagram. Agree the definitions. Describe relationship of diameter and radius as a ratio (2 to 1, 2:1). We will explore whether there is a similar relationship between the circumference and diameter.

**Group Activities**Use the ‘Ellipse in a Circle’ in-depth problem-solving investigation below as today’s group activity.

Or, use these activities:

-- Children draw circles, measure diameters and circumferences with string and work out ratio. Pi is introduced.

**Day 2 Teaching**

Children draw different quadrilaterals and describe them. Together identify their features then name the different types of quadrilateral. Classify these according to their properties.**Group Activities**

-- Children make a range of quadrilaterals using art straws. Copy into books and identify features. Sort with sorting tree or Venn diagram.