What happens to a substance during a physical change?

In a physical change, a substance's chemical makeup does not change. For example, a little girl accidentally snaps her crayon while drawing. Nothing about the crayon was chemically altered, only its physical form was changed.

However, if the little girl put the crayon in the oven, then that would be a chemical change.

During a physical change, the substance doesn't change completely. It's appearance changes as well as it's state. This does not include the bonds.