The window that Ernest T. Bass breaks with a rock in the very first scene is clearly made of paper, yet we hear the sound of glass breaking.
Romona brings outside the rock that was thrown and is handled by a few people. Barney explains about checking for fingerprints by the boys in the lab. The rock is handled again by Mrs Wiley and Mr Schwamp. A few seconds later, the rock is dropped. Barney pulls out a printed handkerchief to pick up the rock. When they return to the sheriff's office Barney puts the rock on the desk however this time, the rock in in a white handkerchief.
When Andy, Ernest T. and Barney are outside at Mrs. Wiley's party, the Griffith house and garage can clearly be seen right next door. In most episodes, Clara Edwards lives next door to the Griffiths.