We have gone thru this in the past year with our DD 17. The law in California is you can not have anyone in the car for the first year! You can transport sibling with a note. We also have cellphone/texting laws for teens.
We did a driving contract with DD.

I think this was the best thing we did because she knew what expected of her. Plus, we had in writing what we ALL agreed to. It was a long note about what she had to do to be allowed to drive: good grade, good behavior, job, pay insurance, run any errands we asked of her, etc. We explained that driving was a priviledge that you earn! That can be taken away if you do not follow the rules. Lucky for us.. she is a rule follower!
*For the 1st 3 months she was allowed to drive anywhere in our city, Not on the freeway! She was NOT allowed to use the radio! She had to call when she arrived and when she left.
*After 3 months, we added the town just north and south of us. She was allowed to use the freeway. Plus, she could use the radio. She still had to call when she arrived & when she was leaving.
*After 6 months, we added another town north of us and 1 south of us. She was also allowed to take a sibling to run a short errand. She only had to call when she was leaving no longer when she arrived. Sometime she had to drive a sibling to school.
*After 9 months, we added 2 more towns.
*At the one year mark, she had no more restrictions unless it was because of behavior!