Habah L’taher Misayin Oso. You must be a very special person to take this on. Firstly, (as some other people mentioned,) dont bite off more than you can chew. I’m not encouraging doing less, but if you feel at any point that this is too much, then just concentrate on one thing. The same way a person who is trying to increase kavana in davening should concentrate on one Tefilla or Bracha.
Is it possible for you to do something after school? Like get involved in a Chessed, maybe through a program in your school, help a friend/neighbor who has young kids/had a baby recently, find someone who needs extra help with homework. The point is if you cut down on your time at home, maybe everyone will “forget” you’re doing something out of the ordinary if you are in a rush to eat supper, finish homework etc. Even study by your friends houses, if that will get you out of the spotlight.
Another idea (if this is your thing) if you have a black skirt which you aren’t wearing, maybe do something with it. Make a belt, a headband, even something to cover your notebooks.
Hatzlacha!
(sorry, that was very wordy!)