Bart asks if World War I was "the war with Hitler." While Hitler is generally associated with World War II (as he ruled over Germany at the time) he DID in fact fight in World War I, so Bart's statement is not wrong.
The "Future Sphere" which Marge and Lisa ride is a parody of EPCOT's iconic Spaceship Earth.
Lisa asks "what happened to the Bart Simpson who put moth balls in the beef stew?" That is a reference to the song Do the Bartman (1990) in which Bart claims to have done exactly that.
The "Home of Tomorrow" attraction is based on the House of the Future, which was actually located at Disneyland rather than Epcot Center.
The map in the classroom shows the nation of Austria-Hungary. This means the map is from at least 1918 as this is when both nations were separated to be their own nations.