Well, the Robins have left their nest and haven't come back. The kids enjoyed watching the birds get fluffier and larger every day. Amazingly we never heard them cheep, and they didn't make a mess beneath the tree.
A few days ago we saw the last bird flop out of the tree and neither Mrs. Robin nor the babies have returned. The nest did somewhat fall over in the wind and we've been able to see the inner workings of the nest, which even my husband admitted was "cool."
With my kids' new-found knowledge (and love) of birds I'm planning on checking out the book The Robins In Your Backyard or Backyard Birds so the kids can enjoy learning the names of the other birds we see in the front yard. Thankfully the loss of the birds has been tempered by the frequent visits of bunny rabbits in the yard!