I'm reading Chaim Potok's The Chosen and have come across (in chapter 1) the claim that, during the Great Depression, in Brooklyn,
[e]very Orthodox Jew sent his male [high-school-age] children to a yeshiva, a Jewish parochial school, where they studied from eight or nine in the morning to four or five in the evening… Hebrew studies in the mornings and English studies in the afternoons.
Is this true? My impression — though I'm not sure on what it's based — has always been that most, or, at least, many, Orthodox Jewish boys at that time attended public school and got Torah education after school (often at a "talmud torah" designed just for this after-school purpose).