When I say allot, I mean allot.
And what you really should say and mean, is, "a lot".
Really? You're going to pick the OP apart for that instead of helping him
To the OP, a number of things could be causing the dark photos.
As was said, the aperture could be to small(too high of a number). If the lens does not have a very large max aperture and she is shooting in low light, opening it up all the way may not work.
As was said there may be some exposure compensation dialed in without her knowing it.
She could be shooting in manual, and if the shutter speed/aperture/ISO are incorrect or any combination of the 3, she'll get an improper exposure.
Post a photo if you can, and what lens she's using. This would help us diagnose the problem. I have to think it would be VERY frustrating to have ALL your images underexposed.