??? Of course it would be acceptable, indeed expected of her especially since it is a significant element of her job description (maintaining classroom control and conforming with the administration's program).
In fact, her superiors should quickly realize her intentional actions were clearly contrary to management's published intentions - normally grounds for termination, depending on who is in control.
(It is entirely possible that I misunderstand your statement or the context in which its made.)
To rephrase, should the teacher teach the controversy at all to grade school children? And if she should, is it acceptable to present only one side?