Are You Afraid of the Dark (1992)

Two siblings, Jazz and Augie, are sent to boarding school while their parents are away. They immediately notice that the school is quite different and has some rather strange rules. For example, only calm, soothing tones are allowed inside the school and the students are only given the option to eat something called 'sponge' for meals daily. Jazz and Augie soon learn why the owners are so strange and have these odd rules in place.