Rusty Stevens makes a blatant mistake and catches himself. This happens when Ward is calling a cab. He sticks his tongue out at Beaver just as Ward is talking. He makes an oops face, laughs, then looks straight at the director. Thirty seconds later he sticks his tongue out at Beaver, when he is supposed to.
When calling for a cab, Wally assists June in conveying that the Cleavers' address is 485 Mapleton Dr.