Peg gets directions from youngsters (5)
I believe the answer is:
teens
'youngsters' is the definition.
(I've seen this in another clue)
'peg gets directions' is the wordplay.
'peg' becomes 'tee' (tee is a kind of peg).
'gets' means one lot of letters go next to another.
'directions' becomes 'ns' (N is an example).
'tee'+'ns'='TEENS'
'from' is the link.
(Other definitions for teens that I've seen before include "Adolescence" , "children" , "Between 12 and 20" , "13-19 age group" , "seven-year period" .)