personally i wouldnt get anything too big
the biger the tank the more maintenance it will require
maybe a 75, 90 or 120 would be nice .
not too big but a very good size tank
it will give you a good amt of livestock choices
and dont forget
the BIGGER the tank the MORE EXPENSIVE the equipment will be
youre parents are great for giving you an incentive for good grades
just keep it up and you can get in to college to get amuch better job than the bulk of your high school kids
trust me
flipping burgers at mickydees is not a good way to spend your time and you will not make enough money to support your new large tank
not to mention the cost of fish ,sand, equip,lights,etc will take time to buy when you work for $5.50 per hour
dont mean to crush your hopes just adding a bit of reality to your decisions