Legally, you can leave when you are 18. You might just want to wait for 2 weeks, then you can leave with whatever your parents allow you to leave with. Understand that when you leave, they may no longer support you. Your job will have to help pay for all your expenses - including medical insurance. Have you priced these things out? And while your uncle and grandmother may be able to provide you a place to stay, a roof is but one expense you will have to bear.

But, if you feel it is sooo bad at home that you must leave, do it on or after your 18th birthday. Only then can you truly make those adult mistakes that many do when they are your age.