Open space in Oxford for Oscar entering miserable Tudor school (8)
I believe the answer is:
outdoors
'open' is the definition.
('outdoors' can be a synonym of 'open')
'space in oxford for oscar entering miserable tudor school' is the wordplay.
'space in oxford for' becomes 'o' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'oscar' becomes 'o' (phonetic alphabet: alpha, bravo, charlie etc.).
'entering' is an insertion indicator.
'miserable' indicates anagramming the letters (I've seen this in other clues).
'school' becomes 's'.
'tudor' anagrammed gives 'utdor'.
'o' going within 'utdor' is 'utdoor'.
'o'+'utdoor'+'s'='OUTDOORS'
Can you help me to learn more?
(Other definitions for outdoors that I've seen before include "In the open air" , "Al fresco" , "Not in a building" , "abroad" , "Alfresco" .)