Old educational establishment disheartened tutor (4)
I believe the answer is:
tech
'old educational establishment' is the definition.
'tech' can be an answer for 'establishment' (tech is a kind of establishment). I am not certain of the 'old educational' bit.
'disheartened tutor' is the wordplay.
'disheartened' says to hollow out the word (remove centre letters) (the middle or heart is removed).
'tutor' becomes 'teach' (I've seen this in another clue).
'teach' with its centre taken out is 'TECH'.
Can you help me to learn more?
(Other definitions for tech that I've seen before include "College teaching practical skills (informal)" , "The practical use of science, in short" , "Kind of college" , "Abbrev. for a college" .)