Millie Davis's character of Ms. O is heavily implied to be immortal. Jack McBrayer - who plays Weird Tom - also played a character in the NBC series 30 Rock (2006) who was heavily implied to be immortal as well.
Weird Tom is said to have zapped "the President" in the 1983 flashback, set on the Canadian side of Niagara Falls. Reagan did not visit Canada in 1983, although he did visit twice in 1981, and once in the years 1985, 1987, and 1988.
Mrs. O's quote "good work, you little rascals," is a reference to the Our Gang short film series, known contemporarily by their alternate name, "The Little Rascals".
In space, the heads in the sky are a reference to the music video for Queen song "Bohemian Rhapsody". Recorded for the television show "Top of the Pops (1964)", the promotional film is considered the first modern music video.
Weird Tom is shown to be 12 years old in the 1983 flashback. In reality, Weird Tom's actor Jack McBrayer was only 10 years old in 1983.