Part of school collapses following regular expulsions (5)
I believe the answer is:
class
'part of school' is the definition.
(I know that school has part or parts class)
I cannot understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for class that I've seen before include "sort" , "Opportunity to learn" , "Fine" , "showing stylish excellence" , "Standing" .)