Obvious answer would be to forget about her. But that's usually harder than it sounds...
If you still want to give it a shot, this is what I would think about doing (whether I'd actually do it is another question

). If you walk past her in a corridor or something, make eye contact, smile and say "hey, I know you...you're in my driver's ed class aren't you? What's your name again?"
Just ignore the nerves that I'm sure would be there.
Edit: or, even better, do the whole "hey!" raise your hand and then high five...the strategically-placed person behind her. Always wanted to try that
