FinalsToLand: I cant remember the age limit now but i would be suprised if a 14yr old will be allowed to trvl without u/m assistance
It'll obviously depend on the individual airline's policy, but BA regards any pax over 12 to be capable of travelling unaccompanied without assistance. Go to
Ask BA and search for Answer ID 896. Of course, it may still be a good idea to pay for the assistance/supervision, but it may not strictly be necessary.