Do second language before end of schooling (7)
I believe the answer is:
shindig
'do' is the definition.
(I've seen this before)
'second language before end of schooling' is the wordplay.
'second' becomes 's' (common abbreviation).
'language' becomes 'hindi' (Hindi is an example).
'before' means one lot of letters go next to another.
'end of' indicates one should take the final letters.
The last letter of 'schooling' is 'g'.
's'+'hindi'+'g'='SHINDIG'
(Other definitions for shindig that I've seen before include "Bash" , "Hidings (anag) - party" , "Big lively party (colloq.)" , "Noisy knees-up" , "Large, lively party" .)