1. Were you ever explicitly taught how to organize and write a report (book report, science report, whatever) in grade school/high school?
Yes. We had to do “book reports” with paragraphs with “topic sentences” as early as grade school and “research papers” with short bibliographies in high school. But I really learned the basics of report writing in AP English as a high school senior.
2. Were you ever explicitly taught how to organize and write a report in college or grad school?
Undergrad, no. I tested out of low-level English Composition. I learned the basics of legal writing in law school.
3. If yes to either 1 or 2, were you taught how only in English class, or did other subject teachers also make an effort to correct grammar, spelling, organization, etc. in addition to the subject matter?
Only in English, IIRC. But I was always a pretty strong writer and IME the expectations for writing in non-English classes was always pretty low, so I would not have expected to receive much correction in those classes anyway. There was more attention paid to basics of writing like grammar and spelling in Legal Writing in law school than there ever was in non-English classes in university.
4. What major were you in college, and how long ago was that?
English Lit. and History, 1992, Law, 1995.