I have been trying to become lucid for 2 weeks now, and studied for exams right before bed the last two nights with no results. I'm not saying that you are incorrect however, I think you might be onto something because although my dreams were not lucid, they were still extremely vivid. Training your brain to memorize right before sleeping may increase the chances of dream memory while sleeping. My exams were for chemistry (which involves math), and Biology. I might try this again tonight!