 You can help a child understand that shapes can be split into separate shapes by helping them fold paper. To start, you can cut out a square of paper. Then you can help the child fold the paper in half, vertically like this. You can ask the child, what shape did we turn the square into? And they can say, a rectangle. Then you can have the child open the paper back up, and you can point out the line they just made with the fold, and how it splits the square into rectangles. You can ask, how many rectangles do you see? And they can count, and say, two. Then you can work together to fold the paper in different directions, and see what shapes it makes. For example, you can help the child fold the paper in half horizontally, and they may see that it is also a rectangle. But when they open the paper back up again, now they may notice that there are four squares. Or, you and the child could fold the paper diagonally to make a triangle. You could even have them fold it in half again. Then when they open the paper, they can count how many triangles there are. This activity helps a child learn how shapes relate to one another, and that one shape can be divided into many different shapes.