A great idea asking and i wish you luck but, a picture is a tough find...
Think of various places, events, etc... that involve photo's being taken...
For starter's, try looking for any schools she attended, their locations and when it may have closed (which i am almost positive but, not 100% it will be). Anyhow, that town's public library may have old photo's from that school of various grades...
Just a suggestion and i wish you Happy Hunting!