We don't usually stop to think about how or why we sort things in our daily lives - we do it automatically. But it is a skill that children need to learn. At home, we sort things in different ways for different reasons, often to store them in limited space, and so that we can find things easily - for example, pots and pans in the cupboards, clothes in drawers, books on a bookshelf.

When we sort objects, we put them into categories according to particular criteria - for example, their size, shape or purpose. This unit looks at sorting objects by shape. It shows flat and solid shapes with curved edges and straight edges. Children learn the correct names for shapes and find particular shapes among collections of everyday objects.

You can help your child by encouraging them to talk about the shape of objects and to begin to use the mathematical names of shapes. For example, what shape is the box of cereal? What shape is each face of the box? When you put away the shopping, let your child experiment with stacking objects: which shapes stack easily and which ones don't? Look together at the shape of food packaging on supermarket shelves and how the objects are stacked.

Shapes and their properties are an important part of maths, and categorisation is important in many school subjects (including maths, science, geography and technology) to help us understand and describe the world around us.