Average weight for 16 year old girl?

An average weight is based upon height. So there are a variety of "average" weights for a 16 year old girl.

A more important question is "What is the appropriate weight for me?", and for that you shoud consult your family physician.

Unless your weight is such that your personal physician tells you that you are facing disastrous health problems and must lose weight...then congratulations, you're fine.

Do not fall for Hollywood hype or the plethora of dietary scaremongers out there. Check with your doctor if you think you need to, then just be yourself.