Shout about ridiculously young leaders (3)
I believe the answer is:
cry
'shout' is the definition.
(I've seen this before)
'about ridiculously young leaders' is the wordplay.
'about' becomes 'c' (abbreviation for 'circa'**).
'leaders' suggests taking the first letters.
The initial letters of 'ridiculously young' is 'ry'.
'c'+'ry'='CRY'
(Other definitions for cry that I've seen before include "Sound of pain or grief" , "Shed tears" , "Call" , "Blubber" , "Don't . . . over spilt milk" .)