Sorry, but I got the same thing going here and I'm in college.
In my last year of high school, I was playing call of duty a lot and ignoring my school work. I did fine on the AP tests (most of my classes were AP) so everything turned out alright (I just had lower grades on my report card, which didn't matter to me). Over the summer I was working to pay for college and playing call of duty whenever I could (which was a lot).
But now I get a darn hour a day because they apparently don't trust me to do my school work. My best friend got online a week ago so I figured I'd borrow the rest of my time for that week and spend like five or six hours playing with him. My parents let me do this over the weekend so I thought it would be fine.
But no, I get grounded for an additional week. I have to wait another week to f*cking play. You have no idea how ridiculous it is.
Guess how they know how time I spend online? If they did something like what your parents do where you write the time down, I'd have no problem lying about it. But my dad has this darn program on his computer that tells when a computer in my house is being used along with my ps3. So they are tracking how much time I spend on the computer/ps3. So on friday I went over my friend's house after a dentist appointment and spent the rest of the day there.
Well guess what? Halfway through the day my mom decides to go through every single person in the phonebook that had my friend's last name to call them and find out where I was because I didn't turn my cell phone on (I absolutely hate having to charge it every couple of days).
I seriously feel like I'm being monitored and controlled like I'm under some dictatorship or something. I gotta say at this point the only reason I'm still living here is because otherwise I'd have to move out and find an apartment and pay for it myself without their help. They told me they'd only help if I stay in college.
So I feel bad for you. I think I, more than anyone, understand where you're coming from. But if all they make you do is make you write down your time, then you can find ways to get around it. If they don't check up on you a lot or anything, just play more and write down less time. Play after they go to bed and don't write it down. Be sneaky. Play off the trust they have in you. If they put a timer next to your computer or game system and walk away, adjust it and give yourself more time.