Michelle (the Olsen twins) is certain that there will be nothing but fun-and-games when Joey (David Coulier) agrees to act as substitute teacher at her school. But Joey takes his job very seriously, and before long a humiliated Michelle finds herself exiled to the principal's office. Meanwhile, it looks as though Danny is going to be lead guitarist in the new band organized by Jesse...until a talented newcomer named Viper (David Lipper) comes along. ~ Hal Erickson, Rovi