Here's the Jan Sleet mystery story for this month. A bit late, I know, but the first of the month kind of sneaked up on me.
The story is called "The School Mystery." In it, Jan and Marshall go to the U-town School, where the great detective addresses a class, on a variety of topics, and they run into two old friends.
And (strictly for educational purposes, of course) Jan Sleet quotes an Irish playwright, and an English novelist (twice).