The only suggestion I will make is this, which is basically a recapitulation of everything that's already been said:
We often feel that when people expect us to do good things, that we are obligated to do them. This is not the case. At the end of the day, no matter what people expect of you, your choices are still your own, and there's a reason that you make the ones you do. You are given the choice to do good things, or not to do good things, and ultimately what reflection will lead you to realise is that you shouldn't be doing good things for the sake of others because they expect it of you, nor should you do good things to keep yourself out of trouble with your folks, nor should you do good things because it is convenient at the time and serves a personal end: you should be doing good things for the sake of goodness itself. Sometimes its okay to say 'I will cause [myself] more harm than I will give [others] goodness, so I really ought to (stay home and do homework)/(sit down and relax so I don't burn myself out)/(focus on task a because it is more important than task b)'. My opinion on the matter is that your only real obligation is to Goodness as an ideal, which you sometimes have to fulfill in a manner that people will see as totally selfish -- but fuck them and their shortsightedness -- the trend of your actions over the course of your lifetime will determine whether or not you have succeeded in being the best person you can be. Let them call you selfish and uncaring; because you will know that you aren't, as will anyone else willing to look beyond the present. I would even go so far as to say that fulfilling the short-term desires of other people might even hinder your ability to do greater things later on in your life, and as such, might lessen the overall goodness that you are capable of doing - your obligations then, lie not with those individuals, but with the higher long-term cause: if you sway to the will of the individuals, and in doing so do not fulfill your duty to Goodness, then you're basically failing them anyway, as well as failing yourself.
You are completely right to be frustrated when someone demands you do something now that will adversely effect your future. As Emerson would say, 'you will always find those who think they know what is your duty better than you know it' but in reality you are the only one who, through contemplation of nature (read: human nature, and the divine laws of nature) and intuition, know what's best for yourself. People might be pissed at you for not doing what they want, but what they want may not be what is truly good.
As far as I'm concerned, experience is the only way we come to know truth, and there are times when we learn what is good by experiencing 'bad' things. Try to keep everything in perspective. Obviously, rebelling in a destructive manner by becoming a hoodlum/vandal/thug/drug addict isn't going to be good for you, and you realise that, which is why you've already said you wouldn't go that far. It wouldn't be good for others, but it wouldn't be good for you either. My only word of caution is that you should not presume what you want to be what is good; we all must learn to desseminate the two, and strive to do what is best. Sometimes that will be what is best for us, sometimes that will be what is best for others; but we should all want to do what is best, always, even though now and then it may be inconvenient to us.
If I may alter what julianamendoza concluded with slightly... become Good independent of others' opinions of what constitutes good.
Anyway, best of luck to you
Cheers.
I'll take it though! 
