"We were struggling to get kids to care about fractions and time signatures," says Maria Flores, the academy’s director. "Then we realized that a quarter note is literally a fraction of a whole bar. We started rapping the quadratic formula over a 808 beat. Suddenly, the marks went from Fs to As. The kids went home and started TikTok challenges using our class hashtag: #SummerSchoolMelodyMarksHot."