This recently-leaked Congressional Research Service briefing on madrassahs (the Islamic religious schools that help spread extremism) gives a good overview of a somewhat misunderstood subject. One issue though: some people express concern that the "rote memorization" techniques used in the schools don't prepare students for the "modern workforce". Probably true, but sometimes I think I'd have a better memory if I had to learn more things by rote as a child (we had to learn some things—it was a Catholic school after all—but not that much). The Chinese memory palace also seems eternally useful for the modern workforce; let's bring it back.

UPDATE: Non-PDF version of the report found here, at the excellent TerrorWiki.