Facebook privacy from parents.?

[jojorocksyoursocks]

I am 17. I have a facebook account, and my parents still log in and check everything I am doing. I am wondering if there is anything I can do about it, as I am a good child and I see it as an invasion of privacy. Can I do anything about it now, or even when I turn 18 soon?
oh and my dad is good with computers, and he always finds out what my password it. it doesn't matter how many times I change it. he has this computer program thing. it's not a problem that they log into my account, I have nothing to hide from them, but I just want privacy.
he has a program on my computer that automatically saves all my passwords. I don't know what it is. I have searched for in on my computer, but I am unable to find it.