I'm not a pro either but I'd say the lighting isn't doing you any favours. You seem to have shot the shadow side of the subject, which is seldom the best option, and the light seems to be dappled. Most of that can be corrected in post processing though.

Perhaps circumstances or timing didn't give you any options, but for those times when you do have options, the success (or otherwise) of this type of shot depends to a large extent on the lighting. Having said that, you managed to capture a very pleasant and natural smile, which most would say is THE most important thing.

I keep seeing give her some old used camera that obviously no one wanted any more.
This is disturbing as she is now relegated to second class and not worthy of something that is hers.
There are wonderful brand new cameras at little cost with incredible features and the excitement of opening the box of a new camera that no one else has used and abused.
That right there says she is valued and what she desires has value and that there is confidence in her wanting to learn photography. Other wise the message is sent that she is expected to fail thus why waste time getting something new and nice that is all hers.
The exception is if she really wants a camera of yours specifically that she sees you truly value that would be OK but not one of your old discarded cameras you do not want that you have no value for.
It is the wrong message to some young woman desiring to learn and has expressed that desire strong enough to want more than a cell hone to get her a new camera that says this is all yours and not a leftover hand me down.