Hey Hon,
I also do many extra curric things. (orchestra, private cello lessons, work with Oaktree, world vision, running a make indigenous poverty history state wide project, hockey, work for blue dragon children's foundatoin, run the charity group at my school, do model united nations, am exec of the src, in the vocal group, do volunteering etc etc). I go to a selective school and have been in the top five every year so I do understand teh pressures you are talking about. So here's what I do, I dont know if it will work for you though, everyone's individual.
I manage my life through a series of lists.
I have a list that i write at the begining of the week of everything I know I must get done. i write deadlines to get them done by adn I set an amount of time I am prepared to spend on them (kills procrastination!). Then, as I get mor work I add it to my masters list, whilst divising daily lists as I go. Again setting quantities of time I will spend on each subject.
On friday I review my list, make sure I have everythig done and then write up a list for what I want to do on the weekend.
I find this works better than a time table because with teh work I do meeting etc. shift times all teh time so a time table isnt effective.
I stay at school or the library until about 7:30pm at night so I can do all my homework (without computer access) because I find teh computer distracting. Then I come home adn do the work I need to do on the computer (yes I came home early today! I'm sick
)
You need to be motivated and organised if you want to make a whole lot of extra stuff + good marks at school work.
i have a list of goals that I refer to often to maek sure Im on track.
I know this sounds kinda weird and hardcore adn lame, but it's worked for me.. so i hope it's been some sort of help for yoU!
Good luck and take care, remember that stress is just another form of procrastination... look at what you need to do, figure out how and when to do it.. then do it!
Love,
Soph