Continuity Goof: While Mary and Mrs. Stone are working on Mary's hair, they are looking out a window in Mary's bedroom. It is overlooking the front of the house, as they can see the bus Jeff owns that he parked on the street.
In previous episodes during season 5 and earlier, at least one window faces out onto the backyard. As the room doesn't go from the front of the house to the back, obviously, there is a continuity goof between episodes in the placement of this window.
With this episode, we learn Mary won't be a full time character / cast member in season 6. She will be going away to college in the fall.
Joyce Morrill was the reigning Miss Teenage Miami at the time of this episode.