The products in the window of Goober's gas station display the new logo of the CITGO company on them. This episode was made in 1966. In 1965, Cities Service changed its name to CITGO and dropped the old green trefoil logo in favor of the triangular one that you see here.
A previous episode, "Look Paw, I'm Dancing," from Season 6, is referenced at the beginning of this episode when Opie says "That's what you said last year when you forced me to go to that school dance." Andy replies "If you remember, you were glad, afterwards, that you went because you learned how to dance while you were there."