Well you won 2 games so you probably have something going right. How did your defense do ? the reason I ask is because it has been my experiance on every successful team i have had we have had exceptional defense, a great place to start improving is there. next if the problem is being outsized physically, "big teams" work on a spread or option offense use speed and misdirection. involve more players and try to have players specialize smaller guys can give more if they arent tired from being asked to do too much agianst larger or fresher players, stay positive and try a film meeting where you actually single out good play and offer suggestions on mistakes next thing you know the boys win or lose will be football savey and will start impressing you beyond your expectations.

there are some good programs that run a simple single-wing offense that helps to mitigate some of the size and experience issues that youth coaches run into. In So Cal - 6 out of the 8 champion teams ran some sort of Single/Double-wing. There are a couple of books on these - I have read and would recommend Dave Cisar's book