I live in Sittingbourne, so not far from Rainham, i go to groups at my local childrens centre in Milton and there are a few others. Might be worth seeing what childrens centres there are near you and give them a call they can tell you what classes are on and for what age groups. There is also a coffee morning on a monday 10-12 drop in anytime free to go run by the139club and is in Gillingham. I also started to go to baby yoga with my son run by budda buddies on a thursday morning. They are run in terms of 6 week sessions and this one you have to pay for. Hope this helps. If you have found anymore since this post wpuld be great to know as i am always on the lookout for classes/meet ups to do with my son who is 3 months old.