This is the first episode of Season 1 and the first episode of the main series.
The kid Cosmo and Wanda were going to be re-assigned to actually goes to the same school as Timmy, although he is only seen in background shots.
Timmy says it was only 6:04 in response to Vicky telling him to go to bed and Vicky says that it's 9:04 on the east coast. This gives the viewers a hint that they live somewhere in the west coast (which was eventually revealed to be in California in the episodes: Christmas Every Day and Fairy Idol).
This is the first time Timmy sees his Mom and Dad kiss.
Although this episode marks the first appearance of Chester and A.J., their names are not revealed until its sister episode, "Power Mad".
Toy Story - The kid that the fairy messenger showed to Cosmo and Wanda is similar to Sid, due to his appearance and his toy abusing personality.
Big - Timmy wishing to become older is very similar to Josh Baskin wishing to become big.
Something breaking or dying whenever someone says Vicky's name.
The word "creep" or "creepy" being used to describe Timmy after he wishes to be an adult.
Characters injuring themselves while shaving.
Vicky attacking Timmy as an adult when she sees him.
It is unknown how the mean kid knew about fairy godparents.
After Timmy is transformed into an adult, Cosmo and Wanda's reaction was "ewwww", but if you watch their mouths carefully, they seem to be saying something else.
It is unknown where Timmy got a car to drive as he's later shown to not have any money.
When Cosmo and Wanda say "...older Timmy", Wanda's top row of teeth keep disappearing and reappearing.
It's unknown how Timmy didn't forget that he had fairies after he became an adult as according to Channel Chasers and other future episodes, children forget about their fairies once they become adults.
It could be possible that this does not apply here since Timmy did not age himself with an actual aging device (The magic remotes aged people if they pressed the fast forward button).
Also, considering how this was the first episode of the series, it's likely that this just wasn't canon at the time.
The adult Timmy from Channel Chasers looks different from the adult Timmy in this episode.
It might be because Timmy was much older in this episode than the adult version in Channel Chasers.
During the football scene, Timmy's hair that's outside of his helmet keeps diappearing and reappearing.
This episode implies that Fairy Conventions are a place where the fairies meet and discuss topics, though they're shown to be more like a Comic Con-like convention in Cosmo Con.
It is unknown why Cosmo and Wanda didn't go away after the other prisoners saw them.
It's possible that fairies are safe as the prisoners would likely not be believed if they said anything.