So I've thought about my post for a bit and feel the need to make some corrections.
In its purest form, second person is probably speaking directly to the reader; the reader probably shouldn't assume the role of any character in the story (i.e., a child born in a superstitious age). My example might be sort of moot, I guess.
The problem, then, is speaking to the reader without telling them what they are doing and "boxing them in," so to speak. Readers don't like their actions to be dictated for them; unless you're writing a CYOA book, you probably don't want to say "You picked up the sword and killed him" because your reader might not want to. So if you had
to describe the reader figure's actions, I'd pick a time when the reader figure wasn't aware or in control of their actions, IE when they were very young, in a coma, sleeping (though that could get kind of creepy), &c. No matter what you do, you will
be making the reader figure a character, but making their actions believable and agreeable might disguise that a bit? Idunno.
I don't write in second person very often.
One reason that paper might be have been assigned is that avoiding the use of the word "I" can help eliminate passive voice from writing; using the coma example, one would have to write "You worried us" rather than "We were worried." In any case, it's a very nontraditional writing mode, so I can't imagine it would be graded too harshly.
Maybe you could personify a concept, and write to that? But I'm not sure if that would be second person in the strictest sense, either.