Abrupt teacher group of students found in bad shape (7)

I believe the answer is:

misform

I'm a little stuck... Click here to teach me more about this clue!

'in bad shape' is the definition.
The definition suggests a verb in its base form which matches the answer.

'abrupt teacher group of students' is the wordplay.
'abrupt teacher' becomes 'mis' (I am not sure about this - if you are sure you should believe this answer much more).
'group of students' becomes 'form'.
'mis'+'form'='MISFORM'

'found' is the link.

Can you help me to learn more?

I've seen this clue in The Times and The Sunday Times.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.