A wind band is no place for an electric bass. The closest I've ever come was playing double bass with the wind band when we only had one tuba.
Now, JAZZ is another story.
From a band director's POV (that's sort of what I do for a living), you don't include an electric bass for much the same reason that you don't ask the drummers to play drum set for concert band. Tonally and traditionally, it just doesn't work.
Now if she's desperate, that's one thing. But if she's got a decent instrumentation, I wouldn't bother with it if I were her.
As far as asking if you can read music, well, duh. If you can't read music at a high school level, then you can't play in the high school band. That's pretty logical, don't you think?