Like many college professors, Johns Hopkins professor Peter Fröhlich grades his final exam on a curve. For instance, if an 80 is the highest score received on a test worth 100 points, that score is marked as 100%. Lower scores will then be assigned higher values on a relative percentage basis, so a 60 would become a 75, and so on. But what happens if everyone gets a zero? Three classes worth of students decided to find out.