Much cooler than the TeleTubbies (which are now ''passe''):

BBC pre-school education and fun.  Live action entertainment show.
Four brightly coloured "children", two similarly semi-realistic 
"adults" and a "dog" (or two in later episodes).  The action takes 
place at a kind of pre-school playgroup, including singing and 
dancing, craft activities, stories, play and occasional trips out.

Thoughtfully tries to address some of the social interaction issues
which plague children at that age. Moral, but not sickeningly so.

My three year old loves the tweenies, and has learned a lot.

See http://www.bbc.co.uk/tweenies