Series developer Marc Richards originally envisioned the show as mystery solving adventures, with the main characters helping to solve crimes using forensics and Isis saving the day and helping them when needed. After a meeting with Allen Ducovny of CBS it was decided to make the main setting a high school and the principal characters teachers instead.
O mighty Isis!
Because of the frequent use of stock footage continuity errors would often be present. Perhaps the most noticeable example is completely different backgrounds before and after Andrea's transformation into Isis. Her first action after transforming was to take flight and a handful of stock takeoffs recur repeatedly throughout the series.
In syndication, the ending "morals tag" was removed from every episode. The original footage of these scenes is now lost, so when the series was released to DVD in 2007 the scenes could not be reinstated into the episodes; instead, second-generation copies of the scenes were included as a bonus feature.