Burning desire of a man to drop gym classes (5)
I believe the answer is:
arson
'burning desire' is the definition.
(I've seen this in another clue)
'a man to drop gym classes' is the wordplay.
I cannot quite understand how this works, but
'a' is found in the answer.
'man' could be 'son' and 'son' is present in the answer.
A single letter 'r' remains which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
'of' acts as a link.
Can you help me to learn more?
(Other definitions for arson that I've seen before include "Crime of fire setting" , "Criminal pyromania" , "Iniquitous behaviour" , "Crime of fire-setting (5)" , "Malicious fire-raising" .)