Mark, about to take a bit of a holiday from school? (7)
I believe the answer is:
scholar
'a bit of a holiday from school?' is the definition.
I can't tell whether this defines the answer.
'mark about to' is the wordplay.
'mark' becomes 'scar' (mark left by an injury).
'about' means one lot of letters goes inside another.
'to' becomes 'hol' (I can't explain this - if you can you should believe this answer much more).
'scar' going around 'hol' is 'SCHOLAR'.
'take' acts as a link.
Can you help me to learn more?
(Other definitions for scholar that I've seen before include "Pupil - erudite person" , "university type?" , "Person of learning" , "Learned type" , "Academic, schoolboy" .)