Are two 16 year old girls safe in china alone ? If so, what are the biggest dangers ?

I think it's safe if they won't go out late at night. The biggest danger is that they may be stolen if they take too much money or imprtant things with them.

Thank you very much Sara, but if they are with a group is that alright ?

it is OK most of the time. Even when you are with a group, you have to take care of your values. careful makes safety!

You have to be very street smart there. When I was there I seen Groups of people have all there bags taken from them right on the street. On the train people try to walk off with your bags right in front of you. We were in the Holliday Inn in Shanghai, left the room forgot something went back 10min later, the cleaning girl walked right in the room. The room was already done up. My father was almost hit by a car in a crosswalk. Even with a group you have to watch, keep your passport on your skin. My buddy from spain had his stolen out of his bag. They cut the bottom out.