A British scam involving English teenagers, say (3,7)
I believe the answer is:
age bracket
'teenagers say' is the definition.
Although both the answer and definition are singular nouns, I don't see how one could define the other.
'a british scam involving english' is the wordplay.
'british' becomes 'GB' (abbreviation for Great Britain).
'scam' becomes 'racket' (I've seen this before).
'involving' indicates putting letters inside.
'english' becomes 'E' (abbreviation as in OED).
'gb'+'racket'='gbracket'
'gbracket' placed around 'e' is 'gebracket'.
'a'+'gebracket'='AGE-BRACKET'
Can you help me to learn more?
(Other definitions for age bracket that I've seen before include "similarly old people" , "Those people born in a range of years" , "Perhaps 18-30 group" .)