Cartoon fireworks
First we have Tom and Jerry in "Safety Second" where they helpfully demonstrate proper fireworks use. Come to think of it, every depiction of fireworks here is rather inappropriate and inaccurate, but that's cartoons for you, and they are supposed to be funny. Tom and Jerry is predictably old-school (and from the time of legal salutes!), with plenty of comically-timed fuses and blackened faces.
Thanks to k1ley4evr for the clip.
Thanks again to k1ley4evr for uploading the clip.
I think this one is the origin of the line "Celebrate the independence of your nation by blowing up a small part of it." It also shows how not to light a fuse...
Bart's part of the Trilogy of Error episode is centered on fireworks, and is clearly designed as a political message to show how banning fireworks only creates a black market and wasteful police efforts. Or, it's just funny.
Homer puts on a show with his efire system in this one. I personally didn't find this part very funny, the pinwheels in the sky don't work that way, and the dock wouldn't catch on fire from a single little spark, but hey, it's a cartoon, so just watch it and have fun.
Finally, Homer and Bart play with fireworks together in this clip, which I think is the best of all of them because of the dialog. "It's gonna take a lot of fireworks to clean this place up." Indeed...