The information requested falls within the responsibility of the UK Statistics Authority. I have asked the authority to reply.
Letter from Karen Dunnell, dated March 2009:
As National Statistician, I have been asked to reply to your Parliamentary Question asking what estimate has been made of the number of children of school age who undertook part-time employment in each region in (a) 1990, (b) 2000 and (c) 2007. (259757)
This information is not available from statistical surveys or administrative sources held centrally.