Ms. Frizzle 's class creates a unique smell which is bound to take first prize .
Arnold 's cousin , Janet , determined to win by herself , evilly corrupts their smell to a stench that even a skunk would hate .
Ms. Frizzle 's class creates a unique smell which is bound to take first prize , but Arnold 's cousin , Janet , determined to win by herself , evilly corrupts their smell to a stench that even a skunk would hate .