When Wally decides to call The White Fox Restaurant to get an idea of their prices before his dinner date, he asks Beaver to get the phone number from the paper. Beaver reads out, "KLondike 2-3958." Writers of TV shows typically used numbers beginning with KLondike, since the equivalent of KL on the phone dial is 55, a non-existent "exchange," to avoid real people getting unwanted calls when numbers are heard on TV by millions of people. Later it became standard to begin all numbers with "555-" for the same reason.
"The Toy Parade" theme song was jazzed up for the last season.
When Wally tells Eddie Haskell about going to the White Fox Restaurant Eddie tells Wally that if they give him any trouble, to tell them he's Bobby Darin.