Mission 21: Cubes and spheres Ideas • Look for spheres.  Many balls and marbles are perfect spheres, fruits such as oranges are close enough at this stage to be called spheres, as are peas, tomatoes and other fruit. • Explore how the shape of spheres allows them to roll in any direction.  Make spheres out of plasticene or modelling clay.  Compare how they can move with sausages made from the same material. • Look for cubes. Every edge and every face of a cube is the same. Look at some rectangular boxes. Some might be cubes but many will not be.  Stock cubes are good examples as they have very square corners. Shapes such as dice are close to being cubes and can be counted as such for now, even though they usually have rounded corners and edges. • Find out how cubes move. See that they can slide but that they don’t roll very well (although we talk of rolling a dice, a dice is usually a rounded off cube as mentioned above which helps it roll better than a perfect cube). • Try building with cubes and with spheres. What happens if you try to stack spheres? The fact that spheres have no flat surface makes them difficult to stack, although you can build pyramids with them if you can keep the bottom layer steady enough. • Wrapping a cube in paper emphasises the straight edges and corners. Trying to do the same with a sphere emphasises the lack of straight edges. • Put a collection of cubes (building blocks are good if you have them) and spheres in a bag. Ask your child to put their hand in and, without looking, pick you a cube or a sphere. Ask them how they knew which they were getting. Agents find out about spheres and cubes.  This mission focuses on the 3-d shapes cubes and spheres, identifying them and seeing different examples from real life.    Vocabulary: cube, sphere, shape. .