London Zoo has a great balance between education and interaction. This little fella paid us a visit at Penguin Beach. The set up gives you a fantastic view of them swimming, like darts, through the water. Reggie (our 3 year old) was mesmerised and so was the Penguin.
If you want a great day out (and it really is all day) then pay it a visit. So many wonderful things to see, do and experience.