Serial Mom (1994)

Happy housewife Beverly Sutphin has a charmed life - a beautiful suburban home, a successful dentist husband, and two normal teenagers. However, when one of her son's teachers speaks disparagingly of the boy at a parent-teacher conference, Bev runs the instructor over in the school parking lot. Suddenly she has an insatiable taste for murder. Six homicides later, the cops get wise to her crimes.