She caught the words "entirely destroyed," "serious offence" and "investigate at once," Then the principal left the room and Miss Chester turned to the class and began the recitation.
To Eleanor's surprise, nothing was said of the matter that day.

School was dismissed as usual, and the girls went out without dreaming that on the morrow they would all be placed under suspicion until the person guilty of the outrage was found.
The following morning, after opening exercises, Miss Thompson stated briefly the destruction of her paper.
"I was out of my office barely ten minutes," she said, "yet when I returned some one had ruthlessly torn the essay to bits and left the pieces piled in the middle of my desk.

As I had spent considerable time and research in getting the subject matter together, the destruction of the paper is particularly annoying.

Whoever was contemptible enough to engage in such mischief must have known this.

It looks like a deliberate attempt to insult me.