This episode introduces Georgie's special talents that would lead to his eventually becoming "Dr. Tire".
Sheldon says, without further explanation, that his favorite prime number is 73, just as he did in "The Alien Parasite Hypothesis (2010)". But in "The Big Bang Theory", he gave an explanation.
The video game console is called "Tanoshi", which is Japanese for "fun".
Sheldon sits in the back seat of Meemaw's car despite nobody sitting in the front passenger seat. In the '80s, most kids still sat in the front seat and cars didn't have airbags yet. With the advent of airbags, it was no longer safe for kids to sit up front, so kids had to sit in the back. Sheldon got carsick in other episodes, including in The Big Bang Theory (2007), so he'd probably want to sit in front, as you're less likely to get sick. However, it was established in multiple episodes that Sheldon prefers to sit in the back seat because, statistically, it is safer.
Throughout the series, the writers pepper Sheldon's character with subtle indications of his ASD level. In this episode, it's revealed that he doesn't have a "Top 5 Cereals" list or even a "Top 10". He has a "Top 6".