Just FYI, I'm 18, with a clean driving record and such (no tickets, etc). I pay by year and its about $1833 a year (or $157 per month for me)
By the way, thats NOT full coverage. I'm not sure where you live, but in Canada
, we have a GDL drivers license program. After you take that test (I'll take mine in about 2 weeks) your insurance starts to go down (providing you have a clean record).
If I were you, I'd start under my own insurance as soon as possible. That way (providing you are a good driver and no accidents/tickets) you can build a record for yourself.
Lots of kids at my school are under their parents insurance, and even though they don't pay for it, its not really helping them out in the long run.
For someone who may not have the money to pay for it right away, its an alright option, but it is good to build your own record so IF you have an accident sometime, the insurance company can look back on your records and see that you are a good driver, and give you a bigger break
Just my two cents worth...