No one wants to be Voldemort, but everyone wants Hermione's brains! Have students do a timed multiplication test with that level—for example, all multiples of 2, all multiples of 3, etc. Students must get 80% OR higher to move on to the next person; in other words, they must pass that level 6 times to move to the next level when students move on to be Hogwarts Bound! They should know ALL of their multiplication tables! Small rewards when doing this is fantastic, such as getting a piece of candy