The motives of these parents vary, many parents don't like the curriculum being taught to their kids, or are wary of the threat of peer pressure or the presence of drugs or violence lurking in too many of our schools today.
For my future I have no concern, and as a true philosopher, I never would have any, for I know not what it may be: as a Christian, on the other hand, faith must believe without discussion, and the stronger it is, the more it keeps silent.