Begin by counting objects. Count only the same objects when you are forming group. Ex: Count a group of ten pencils, a group of ten erasers and a group of ten crayons. After counting the groups, line each group of objects in a row, one exactly above the other. Line the group of ten pencils first. Then immediately below them, line up the group of ten crayons. As you count each crayon, point out that the first crayon can be partnered with the first pencil, the second crayon with the second pencil and so on until you get to the tenth crayon. The fact that all the pencils had a crayon for a partner means that both the crayons and pencils had an equal amount in each group. Now do the same with each eraser. Point out that it can partner off with one crayon and one pencil. At the end each crayon and pencil set had an eraser. This is because the groups were all equal.