The main characters are usually preteen boys and girls who experience supernatural phenomenon which are often mentioned in other books but are never fully referenced.
The school is run by Dr. Morthouse, who has gained infamy from the students due to her cold, cruel, and frightening personality, along with the possibility that she has a silver fang in her mouth which they often catch a glimpse of.
The vice-principal, Mr. Hannibal Lucre, is overly sweet to the students, and is known for the damp, squishy noise his sweaty hands make when he rubs them together.
The kinds of threats the kids usually deal with are ghosts, vampires, and mummies, along with one-of-a-kind creatures such as a demonic Easter bunny, a haunted school bus, resurrected dinosaurs, wish-granting spiders, a skateboarding Skeleton, and other such monsters.
Other children's horror series from the 1990s include Are You Afraid of the Dark?, Spooksville, Ghosts of Fear Street, Bone Chillers, Deadtime Stories, Shivers, Spinetinglers and Shadow Zone.