Dude… my friend’s and I get together (video conference) to watch the film every year in late October. It also features Charolette Rae (the matriarch on Facts of Life) Dianna Rigg (Queen of Thorns on Game of Thrones) and Fariuza Balk (The Craft, Waterboy etc.)
The Worst Witch was a series of books though that Rowling absolutely read before “coming up with” a boarding school for magic using students, but get this: In Rowling’s imagination its BOYS instead of girls who are the main focus, and the protoganist is the messiah instead of a girl screw-up with a heart of gold. Its not in the film but there are houses with colorful characteristics, the protoganist is from a non-magical family and the scary, raven haired potion teacher seems to hate the protoganist while the kind, grey haired headmaster is patient and understanding. She has two friends in the invisible (to non magic users) castlesque boardings school thats surrounded by a forbidden forest where she hangs out with two friends, one who’s straight laced and academically sharp and the other who’s a bit goofy.