She is indeed a little high up in the frame... Generally speaking it is better if the eyes are on a line two thirds the way up the picture. In her case I know you were trying to crop her long, so the higher eye position would be fine but you needed just a little more space at the top. Couple of inches would be nice.
You probably could have take that off the bottom no sweat.
The dust on a digital print is easy to cure with a clone tool or an airbrush those are easy to use and part of almost any photo editor.
The softness can be the Intentional or not. If not, it could the focus of the camera or the enlarger or even the scanner.
She is posed well in my opinion, and appears to be relaxed with you... There is no shadow on the back ground and her face appears to be is well lit. I like the shot very much but would have gone for a sharper image personally. Otherwise it is very acceptable I would say for a school project.
On the print, for the dust try to find yourself some photo dyes. Spottone is the one that comes to mind. Looks like you only have a couple of dust spots shouldn't take more than two minutes to spot them out.
Good luck and stay at it.
