Replying to Parents Getting Lamer As I get Older? Not really LM related

Basically....

all throughout middle school my parents were pretty restrictive and shit, then when i got into high school, they got pretty cool, letting me stay out late , go to some parties, hang out with friends when i wanted to and what not... still not cool with drinking and smoking (i did anyway) but whatever... They said when i got older, like 17ish, i could drink with them and so i was like "cool, whatever"

but now i'm a junior, and basically this summer they were hella cool, let me take their cars whenever, stay out all night, etc... but then school started and about around the start of the new year, they got all lame and restrictive again, they won't even think of letting me drink, even with them, and they bitch at me all the time about responsibilities and how i'm fucking up (i'm not)

anybody else had this happen to them? or advice on how to get over this hump?

btw i'm 17