My daughters attends a lovely community based playgroup www.newsteppingstones.co.uk/ in Mortlake which usually has a long waiting list but due to a number of parents moving overseas it has a few spaces available in September. It is a Non-profit making playgroup with a 'Good' Ofsted rating and has a lovely community feel. If you are new to the area with a child turning 2 1/2 it is well worth a look.