At least three episodes were never fully realized. According to Sir Michael Palin and Terry Jones, "The Seawolf", "Rizzo the Wonder Dog", and "Dracula at St. Dominics" were started, but not completed.
The first season was mostly shot on film, which was unusual for a light entertainment show and cost twice as much as a conventional situation comedy. To save money, three episodes were shot in one financial year and the remaining three were shot in the next.
Michael Palin kept the Claw from season one, episode six, "The Curse of the Claw", before donating it to the Pitt Rivers Museum, Oxford (part of the University of Oxford). It is now part of the permanent collection of objects from around the world. Unfortunately, it's not on public display.
The highly successful TV series evolved from a half hour comedy scripted with Terry Jones called Tomkinson's Schooldays and the series won the Broadcasting Press Guild Award for the Best Comedy or Light Entertainment Programme of 1977,