Nena has had a bad day at school after doing poorly on a math quiz. Her uncle, El Mundo the Great Wizard soon realizes that Nena's math force is weak. Nena is determined to learn her arithmetic facts. El Mundo is concerned that Nena will rely only on memorization so he brings out his magic clock to call upon some Great Thinkers to help her out. With help from Archimedes, Galileo, Leonardo da Vinci, Mozart, and Cleopatra, Nena soon realizes that understanding math is much more than memorizing rules. Mathematics can actually be exciting!