Disorganised start to school fair around noon (8)
I believe the answer is:
slovenly
'disorganised' is the definition.
(I've seen this before)
'start to school fair around noon' is the wordplay.
'start to' suggests taking the first letters.
'fair' becomes 'lovely' (I've seen this before).
'around' is an insertion indicator.
'noon' becomes 'n'.
The first letter of 'school' is 's'.
'lovely' going around 'n' is 'lovenly'.
's'+'lovenly'='SLOVENLY'
(Other definitions for slovenly that I've seen before include "Dirty and slipshod" , "Untidy, unkempt" , "Untidy, careless" , "Untidy, dirty" , "Habitually dirty and unkempt" .)