My 7 yr old's face has a bump on forehead and one on the cheek. What could it be?

Many things. Depends on what the bump looks like: is it red, swollen, draining, tender to touch or growing in size? If so, please have it checked by a doctor soon.
Many possibilities. There are many possibilities. Odds are it isn't anything to be concerned about. Skin cancer in children is very uncommon. However, i would suggest you have it examined.
Bumps on face. Because kids play with other kids that may have infections like molluscum contagiosum or warts, a pink or skin-colored non-painful bump on a healthy child's face would probably be one of those. This is particularly true in a child with eczema, dry skin or asallergies however, there are many things that bumps could be, so they need to be looked at by a dermatologist to make the right diagnosis.