This a great idea to keep your little poppits busy and educated!
Bag yourself a book on garden birds, (I have found loads in my local charity shop). Then if you have a garden head out there with the kids, (if not you could go to the park). Set up a secret bird watching den and if you have some give them some binoculars.
Now your little poppits need to be really quiet and see how many birds they can spot, and hopefully you may get a cuppa or two in!