After getting his hamburger, Bruce pulls the top bun up to show the underside of the bun that there is no mustard. After the scene shift, he is holding up the lettuce as well as the top bun.
(Around 31 minutes) Billy is watching the woman swim in one of the lanes marked out by ropes but after he blows the whistle the ropes have completely disappeared.
The song "(I Just) Died in Your Arms" by Cutting Crew was released in the United States on 1 January 1987, but this episode takes place in June 1985. However, the song wasn't being played diegetically.
Hopper is shown watching an episode of Cheers that shows Sam and Diane discussing the character of Dr. Frasier Crane. Frasier did not appear on Cheers until September of 1984. This episode takes place in June of 1984. But at the very beginning, after the opening credits run, it says "one year later" meaning it is now June 1985 and Frasier had appeared on Cheers.
The phone call received at the newspaper office is incorrectly indicated by a lit red button. For this series of office phones, the red button is actually the hold button. Instead, one of the five clear buttons should have been blinking indicating an incoming call, and could not have been answered by merely picking up the receiver without that button being in the pressed-down position.
One of Dustin's toys is a Transformers Ultra Magnus, which wasn't released until Summer 1986, a year after its appearance here. A different colored version of this toy existed in Summer 1984 as a Diaclone Powered Convoy toy, a Japanese toy line from which many Transformer toys originated.
In the first scene of the closed down Radio Shack, the car on the left of the screen has a distinctive tail light lens identifying it as a 1988-1991 body style Ford LTD Crown Victoria. This episode takes place in 1985.