Disgrace is able to stop boys regressing (7)
I believe the answer is:
scandal
'disgrace' is the definition.
(scandal can mean disgraceful behaviour or news)
'able to stop boys regressing' is the wordplay.
'able' becomes 'can'.
'to stop' indicates putting letters inside (stopping can mean blocking a gap).
'boys' becomes 'lads' (lad is a kind of boy).
'regressing' shows that the letters should be reversed in order (to regress is to go backwards).
'lads' written backwards gives 'sdal'.
'can' placed within 'sdal' is 'SCANDAL'.
'is' acts as a link.
(Other definitions for scandal that I've seen before include "Public outrage; gossip" , "Shocking disgrace" , "Rumour, gossip" , "outrageous behaviour" , "Shock" .)