I took a (very serious, literary, and, later to "switch teams," as it were) girlfriend to Equus while we were both in high school. Good thing she also had the fashion sense to dress us both so we'd pass for college students (all black, natch).
I saw Equus on Broadway when I was in High School as well. I was hoping to see Richard Burton as the Dr., but we saw Anthony Perkins who was pretty good. Were you seated on the stage as the jury?