Allows to enter ballet school? (4)
I believe the answer is:
lets
'allows to' is the definition.
(I've seen this in another clue)
'enter ballet school?' is the wordplay.
'enter' indicates the answer is hidden within the clue (I've seen 'entering' mean this).
'LETS' can be found hidden inside 'ballet school'.
(Other definitions for lets that I've seen before include "Allows or causes to" , "we shall serve them again!" , "Yes" , "Leases" , "Permits" .)