Kid chasing black crow (4)
I believe the answer is:
brag
'crow' is the definition.
('brag' can be a synonym of 'crow')
'kid chasing black' is the wordplay.
'kid' becomes 'rag' (I've seen this in other clues).
'chasing' means one lot of letters go next to another.
'black' becomes 'b' (as in pencil classifications).
'rag' put after 'b' is 'BRAG'.
(Other definitions for brag that I've seen before include "Boast about garb" , "Show off, crow" , "Card game - boast" , "game, making > boast" , "popular with 15 [EGOTIST] , no doubt" .)