Study the relationship between the size of an object and the size of its shadow. When the sun shines, shadows can be seen on the ground or a wall, creating an outline of any object that blocks the light. Shadows are so common that you probably do not pay much attention to them. However, there is much to discover if you observe shadows and experiment with making your own. A fun way to learn about shadows is to make a shadowbox theater and shadow puppets.
Crystals are solids that are made up of molecules arranged in a regular repeated pattern.
In some solids, the arrangements of the molecules are random throughout the material. In crystals, however, the molecules are repeated in exactly the same pattern over and over throughout the entire material. This activity provides instructions for making different kinds of crystals. Almost every solid that occurs in nature is made up of crystals. The minerals found on earth have differently shaped crystals.