It's generally cheaper to add your teenagers to your auto insurance policy than for them to purchase their own. If they are going to be driving their own car, consider insuring it with your company so you can get a multi-car discount. And choose the car carefully — the type of car a young person drives can dramatically affect the price of insurance. Also, encourage your kids to get good grades and to take a driver training course. Most companies will give discounts for getting at least a “B” average in school and for taking recognized driving courses. If your teenagers move at least 100 miles from home — for example, to go to college — you can get a discount for the time they are not around to drive the car (assuming they leave the car at home).