Sit badly, like hooligan wasting time in school (6)
I believe the answer is:
slouch
'sit badly' is the definition.
'slouch' can be an answer for 'sit' (thesaurus). I am unsure of the 'badly' bit.
'hooligan wasting time in school' is the wordplay.
'hooligan' becomes 'lout' (both can mean an aggressive person).
'wasting' indicates named letters should be taken away.
'time' becomes 't' (abbreviation).
'in' means one lot of letters goes inside another.
'school' becomes 'sch'.
'lout' with 't' taken out is 'lou'.
'lou' placed within 'sch' is 'SLOUCH'.
'like' is the link.
Can you help me to learn more?
(Other definitions for slouch that I've seen before include "Loll" , "Droop" , "Sit lazily" , "Sit, stand or walk slovenly" , "Lazy and drooping posture" .)