It’s Saint Patrick’s Day and Eddie pinches Melody because she isn’t wearing green.  Mrs. Jeepers doesn’t allow anything to do with leprechauns in the third grade room; she considers leprechauns worse than blood-sucking mosquitoes.  Since Mrs. Jeepers and her magical brooch won’t let him misbehave in class, Eddie decides to cut loose in gym class.  But Coach Ellison, their whimpy PE teacher gives the class to a visiting teacher from Ireland, Mr. O’Grady.  The short Irishman seems to have magic gem stones and likes Eddie’s pranks.  Mr. O’Grady starts teaching them a dance, but ends up showing them a few tricks on the basketball court.  Howie’s grandmother is from Ireland and she tells them the true story of the wee folk, which is about a stolen fairy stone.  The kids decide that Mr. O’Grady really is a leprechaun and he’s come to steal Mrs. Jeepers brooch, which is the magical Fairy Stone!