Back in high school my teacher did the opposite, she gave a surprise quiz that only someone who actually read the book could answer (a different quiz for each of the eight books one could pick for that month's book report). She then got super depressed that so many of her "good" students were caught cheating. Personally, I would read the book a month before the book report is due but would procrastinate on writing the book report so I would use a Sparknotes-alternative to remind myself what the characters names and certain plot details were although I usually ignored any of its "analysis" (e.g. themes in the novel) which I usually thought was pure bullshit from having read the book.