|We're on the Road to D'oh-where||
- When Homer refers to Oregon as "the birthplace of Matt Groening," he mispronounces the show creator's last name as "Gro-ning"; Matt's last name is, according to The Simpsons 138th Episode Spectacular, pronounced "Gray-ning."
- This episode disproves the common fan theory that Springfield is in Oregon because Homer must drive to Oregon from Springfield's location.
- Birch Barlow (the show's parody of Rush Limbaugh) can be seen at Marge's "garage sale" buying Homer's expired pain pills, a parody of Limbaugh's drug addiction.
- Myra, Principal Skinner's secretary, makes her first appearance in this episode. Her voice sounds similar to the late Doris Grau who voiced Lunch Lady Doris.
- Serious Homer is dressed in Homer's conductor uniform from "Marge vs. the Monorail".
- Further, the rings circling Fun Homer are a parody of the energy cage rings that encircled General Zod and his two minions during their sentencing at the beginning of Superman II.
- On the Simpsons' website; it stated that this episode aired on the same date but originally in 2005. This has since been corrected.
- Skinner's car is seen as a pre-owned Toyota Camry, which Skinner quotes that 1995 was a good year for Camry models even though his car spent three months in a lake which he says while admiring it in the school parking lot. It is never seen again after this episode, according to the episode guide it says that the steam leak destroyed it with the school.
- In the German dub, this was the last episode in which Elisabeth Volkmann provided the voice of Marge Simpson. After Volkmann's sudden death in 2006, Anke Engelke took over. The German version of We're on the Road to D'ohwhere is dedicated to Volkmann.
- The last time Homer imagined Bart as a woman was in "Skinner's Sense of Snow".
- The casino credits version of The Simpsons theme, which was first heard in $pringfield (Or, How I Learned to Stop Worrying and Love Legalized Gambling), is heard again at the end of this episode.
- Lisa wouldn't be able to get a job to support herself and Maggie because of her age and child labor laws. Most Springfielders are either really stupid or really greedy. And who's to say that Lisa can't lie about her age in order to find work? Besides, Bart got jobs in episodes such as "Lisa the Tree Hugger" and "Bart the Murderer", as well as Nelson later owning a bike shop in which he employed people later on in "Loan-a Lisa".
- In one scene, Wendell was sitting in his classroom. Two scenes later, he was practicing with the school band in another classroom.
- Janey can be seen in Miss Krabappel's class, even though she is actually in Miss Hoover's class.
- Much like Wendell, she can also be seen practicing with the school band in another classroom two scenes later.
- Science classes dissect dead frogs, not live ones.
- After the school was evacuated, Milhouse was seen in front of the school with other students. However, he was still in steam tunnels with Bart at that time, so he couldn't be outside.
- We're on the Road to D'ohwhere is a take on the Talking Heads song “Road to Nowhere”. It may also refer to the famous series of Bob Hope/Bing Crosby Road to... movies, which have been spoofed multiple times by Family Guy. This is at least the third time that the Talking Heads have been referenced by the Simpsons, not including "Dude, Where's My Ranch?"
- The song the band class plays is "Louie, Louie", which was also played in "Kill the Alligator and Run".
- The song Flanders sings is the chorus from the hit Andrew Lloyd Webber musical Joseph and the Technicolor Dreamcoat.
- Intellectual Homer, who has been killed by Serious Homer, has written on the floor in his own blood "Ontogeny recapitulates phylogeny". This is the famous statement of Ernst Haeckel's recapitulation theory about the similarity of the embryonic development of organisms to its evolutionary history. Ironically, it has been debunked as a scientific principle. Presumably, Intellectual Homer wrote this before it was debunked, a testament to how long he had been dead.
- 1st Airdate: Sunday, January 29, 2006
- 2nd Airdate: Sunday, May 7, 2006
- 3rd Airdate: Sunday, August 6, 2006
- 1st Airdate: Sunday, February 26, 2006
- 2nd Airdate: Friday, March 3, 2006 (Encore Screening)
- 3rd Airdate: Sunday, April 23, 2006
- 4th Airdate: Tuesday, June 27, 2006
- 5th Airdate: Tuesday, August 8, 2006
- 6th Airdate: Sunday, August 27, 2006
- 1st Airdate: Tuesday, June 20, 2006