Parent here. My kids are older than teenagers, but I'll give it a shot :)
Wait after you knock
Depends. If you're masturbating, fine - I'll wait. If you're smoking cigarettes in your room I probably won't even knock.
Not everyone on the internet is a paedophile who's out to get me
True. The stakes are high, though - and we try hard to protect you.
Don't ask me about school
Sorry, school is your job. Decisions you make now will affect the rest of your life, so I'm asking about school :)
Don't ask me about my career plans
Why not? It's a fair question.
If I do tell you about my career plans, don't immediately try to change them
Agreed. You need to live your own life. As long as you live under my roof I reserve the right to offer advice but it's up to you whether you take it.
Don't boast about how you were the top of all your classes. I'm doing my fucking best.
Agreed. This would piss me off too.
I didn't fail that test on purpose.
True, I know you did your best but if you failed the test something is wrong. I wouldn't be yelling at you, I'd be trying to help figure out what happened and see if I could help.
Yes, I do that that there are less than two months till the exams. I probably know it better than you.
But what you don't know better than me is how failing them will impact your life. It is your life, but you need to be able to make an informed decision before blowing off studying :)
My brother is fucking annoying. I don't want to play with him.
I know he's annoying. I need a break sometimes too.
(Note this assumes I only ask you to play with your brother once in awhile; if I'm doing it constantly that's wrong.)
Also, arguments aren't my fault just because I'm older than him.
Yeah, they pretty much are. You're older than him and I expect you to act that way. If you have a conflict you can't resolve come see me before it becomes an argument :)
If I prove you wrong, don't scream me down and punish me.
Right. Parents are wrong lotsa times. Nobody should be punished for being right.
If I say I need more lunch money, it's not because I spent it all on drugs. £2 a day isn't enough.
My youngest son brought this to my attention once. Next time I went out for a burger I spent way more than I was giving him - he got a raise.