I have a different take on these- I like them very much.
#1 is a great photo. To me, she is looking aprehensive about going out into the big, bad world. Technically, I like the highlights on her hair as they separate her from the background. The people standing in the background further define her as standing, waiting for something. The weakness here is that nothing in the picture really says "graduation." You had to tell us that (see my signature).
#2 and #3- well, either way. #2 looks like you are documenting some event where people are taking pictures. Nothing wrong with that. #3, you happened to be the one taking the picture. Good shots- two pretty girls, obviously friends, obviously happy to be doing whatever they're doing. I like the use of B&W, although I'd be interested to see them in color as well, to compare. (Great advantage to digital photography- shoot everything in color, you can turn it into B&W in post processing.)
As I said, nothing here says "graduation" so that would be my only minus. Put in an album with other pictures that may tell that story, and I think they'll be strong additions. On their own, they're very nice pictures.