Originally Posted by pauldb

You can’t add cash-paying passengers to an award booking, but you can book them separately and if required BA will put a note of your booking reference to record that they aren’t unaccompanied.

Are your plans tied to school holidays. Going far enough south to find some early summer heat is never a waste but if it has to be in the holidays you’ll find less award availability of course (but probably a more worthwhile saving). And their age will have a bearing on appropriate destinations.