I used to do some photographic work for students/new photographers as well as promotional and event hostessing work. It is lots of fun, just make sure whoever you approach/approaches you is legit. You also need to be very confident to survive criticism, stand up to others and try new things.
I'm only 5'6, so high end agencies wouldn't be interested in me. I could always apply for smaller agencies, but the amount of dodgy practice out there scares me. I prefer maintaining it as a hobby/occasional paid work through the contacts I have.
Shoot me a PM with questions if you like