Hey i got referred to this web site a few days ago rosstraining.com its amazing all the stuff he does with out a gym. you dont need weights to get stronger just work your a## off.
good luck in foot ball i was about the same size as you as a freshmen and sophmore but if you just go beserk everyone will be scared and the coaches like people who try.(off topic lol)
its very simple really to win the fight you have to work harder than your opponent.