You may not be able to because of your students, but if I were you I would start opening the egg right away. Likely the chick has passed by now, but if she still is alive, the sooner the better. I can’t tell you how many times I have lost chicks to waiting. Now I help earlier and it has saved many chicks.
Based on the pic I would say that it doesn’t look too hopeful, but waiting any longer at this point definitely won’t help. The chick is either malpositioned or shrink wrapped, or had something else going on. Still though, you deserve huge congratulations for hatching 6 out of the 7 developers - that is incredible for your first hatch!!!!