Fundamentalist sects at least of all the Abrahamic monotheist religions (and doubtless others elsewhere) have often been found to deliberately fail to provide secular education to students, in order to ensure they remain tied to the sect. A couple who left the extremely rigourist Tash sect in Boisbriand, north of Montréal, have been suing the Québec government for failing to address the lack of secular education in that community's schools, in this case worse in the case of the boys (Mr Lowen spoke no French and almost no English).
This Haaretz article is from 2014; the Lowens are in their 40s now. Their eldest is now studying at Université de Montréal on a scholarship; the parents are very proud!
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