However, Milhouse insists on calling the fake girlfriend Alberta and saying that she's from Alberta, so that it'll be easier to not be caught on the lie. This is a reference to the part of the song where Rod (the character who sings the song) says the that his supposed girlfriend, "Alberta", is from Vancouver but slips up at the end of the song by saying, "Soon I'll be off to Alberta."
Homer breaks the fourth wall at the end of the episode saying "Oh, is that what this was?"
The episode is somewhat out of continuity. A theme in the episode is that Lisa always overshadows Bart in everything he does, but in reality, most of the time Lisa doesn't get listened to.
Here's the timeline of Bart's life.
During the second time period, Homer's hair resembles how it looked when he was briefly drawn in Family Guy's art style during his brawl with Peter Griffin in "The Simpsons Guy".
This episode suggests that Lisa was the one who painted the boat painting above the couch, but in the episodes "The Trouble with Trillions" and "The War of Art", it's said that Marge (and later Klaus) painted it.
When Bart is making caricatures, there's a red sign showing some of his drawings, but when he talks with "Nothing" Stu, the sign is gone.
The family is growing up in this episode (also the others) but remain the same voices.
This happened because the viewers wanted to see who the characters were. Bart's voice is different at the end of the episode.