The Theban Mysteries by Amanda Cross

Although Kate Fansler is on sabbatical in this book, she finds herself teaching at her old high school, one of New York's most exclusive schools for girls, when the leader of the senior seminar on Antigone finds herself on bedrest (unrelated to the mystery!). Kate is mystified by youth culture and finds a number of young people struggling with the Vietnam War and the draft. The mystery develops slowly (the body doesn't even appear till the second half of the book), and Fansler's much more adept at spotting the questions of group dynamics (and an elementary form of consciousness-raising) than I was.  Like the other books I've read in this series, the mystery has a certain old-fashioned feel to it, but I enjoyed it.