The Excellency Abdul Baha states in the book “Makatib”: “The Baha’i kids aren’t allowed to go to other schools because it causes abjectness for God’s faith and they will totally be deprived of the Blessed Beauty’s mercies; because they will be educated differently and it cause Baha’is scandals.”
According to this order, the Baha’i kids must be prevented to learn non-Baha’i materials when they can’t decide independently and can’t distinguish bad a good things.
At these ages, they are taught that Baha’ism is the mere prosperous path and its teachings are superior to other faiths. When they are grown, the independent investigation of truth won’t be meaningful for them.