Scene from my novel

Here is a scene I'm thinking of putting into my novel. The idea here is that this is one of a number of scenes which, when combined together, eventually culminate in a mass transformation metamorphosis at around the half-way point of the novel:

Two art teachers, Miss O'Kelly and Miss O'Connor, get turned into waxwork figures in one of the art rooms.
This involves some magical clay which Sharon secretly brings into the school with her.
Unknownst to anyone, this magical clay has a curse on it.
It will also work within an hour or so.
__________________________________________________________________________
At the end of the art classes, a fight breaks out in the corridor.
Miss O'Connor goes outside her classroom to investigate this and finds Miss O'Brien struggling to try and restrain Laura, Niamh, and Gillian from hurting Aisling. (Note: Which actually turns out to be a "staged" fight.)

Unnoticed by either of them, this has now allowed Sharon to slip into Miss O'Kelly's art classroom where she then places the magical clay in amongst all of the other ordinary clay.
Sharon then slips back out into the classroom unseen by either teacher or any of the students who just happen to be around at the time.

A little while later, Miss O'Connor is teaching a class of the junior students when she suddenly notices that her fingers have become mysteriously stuck together.