Grace knew that the principal was still displeased with her.

She was no longer on the old terms of intimacy with Miss Thompson.

A barrier seemed to have sprung up between them, that only one thing could remove, but Grace was resolved not to expose Eleanor--not that she felt that Eleanor did not richly deserve it, but she knew that it would mean instant expulsion from school.

She believed that Eleanor had acted on the impulse of the moment, and was without doubt bitterly sorry for it, and she felt that as long as Eleanor had at last begun to be interested in school, the thing to do was to keep her there, particularly as Mrs.Gray had recently told her of Miss Nevin's pleasure at the change that the school had apparently wrought in Eleanor.
Could Grace have known what Eleanor was engaged in at the moment she would have felt like exposing her without mercy.
During the first rehearsals Grace, secretly fearing an outbreak on Eleanor's part, had been on the alert, but as rehearsals progressed and Eleanor kept strictly to herself, Grace relaxed her vigilance.
Directly after the chums had hurried out of the hall to meet the boys, Miss Tebbs had decided that opening the dressing room on the other side of the stage would relieve the congestion and insure a better chance for all to dress.

Calling to the girls who still remained to move their belongings to that side, Miss Tebbs hurried across the stage to find the janitor and see that the door was at once unlocked.