So the Department of Homeland Security announced today. A few tentative thoughts; if it turns out that I have erred in my understanding of the facts or of the program, I'll update them as necessary:
[1.] Unsurprisingly, student and exchange visitor visas are issued only to people who can show that they really are students and exchange visitors, and at recognized institutions that fulfill the visa program's goals. There are therefore procedures both for certifying and decertifying educational institutions as eligible for the Student and Exchange Visitor Program.
[2.] Equally unsurprisingly, institutions have to provide various information about students and the students' conduct. The DHS letter claims that: