Students of Myself

There are few students in my class. When one considers what the subject is, this isn't surprising. I teach myself.
In other words, I impart to my students facts and fancies based on my life and ideas. It's the least popular class in the university and I doubt it will be funded for another term. But none of that is my fault. I wanted to teach a proper discipline such as ecology, but the authorities wouldn't let me. They insisted that I teach myself; and as a result, I do so.
The students are given an assignment. They each have to write a short piece about how I spend my free time. But this is information I've always kept secret. I can't imagine how they're expected to know anything about my private life, certainly not in detail.
Clearly I'm being spied on. Unless it's guesswork?
I read the essays anxiously.
Yes, only some of them have got it right...