I am trying to enter into a composer`s competition that requires music for concert band that is grade 3 - 3.5. Does anyone know what that means or where I can find out what constitutes grade 3 - 3.5?

If you take a look at this sheet music store you`ll see that some pieces are graded for difficulty, but they also provide images of the pieces so you can see how hard they are.

Try to work on even higher grade music if you can.

http://windmusicplus.safeshopper.com/1326/cat1326.htm?46