The Karate Kid/Trivia

The original film series has examples of:

 * Actor Shared Background:
 * Tamlyn Tomita, like Kumiko, was born in Okinawa.
 * Danny Kamekona was from Hawaii, where the movie was filmed.
 * Dawson Casting: Ralph Macchio was 21 when the first film was made, playing a 17 year old. He was 28 playing an 18 year old in the third film. Not many people noticed thanks to Macchio's boyish good looks and high-pitched voice, making this one of the few effective examples of the trope. Avoided in the reboot, as the kids are actual kids.
 * Executive Meddling: Thankfully avoided in the original film, the studio demanded that the quiet scene in which Daniel discovers a drunken Miyagi mourning his lost wife and child, who died in a relocation camp while he was away being a war hero in Italy during World War II, be cut because it "disrupted the flow of the movie". The director apparently went to war to keep it in the film. Pat Morita would later say that it was this scene that earned him an Academy Award nomination for his portrayal of Mr. Miyagi (Ralph Macchio disagrees, citing his presence in the entire film as the reason).
 * Hey, It's That Guy!: The black Cobra Kai student? It's Lamar Latrell. We shit you not. Karate Kid II had one line roles from such up-and-coming actors as SVU's B.D. Wong, and Clarence Gilyard of Walker: Texas Ranger and Matlock fame.
 * Throw It In:
 * The song drunkenly sung by Mr. Miyagi was one he heard when he was a child. This even gets worked into the second movie as being Miyagi and Yukie's old song.
 * The song playing in the country club Daniel crashes in the first movie is heard again in the second movie, on the radio in the cab ride from the Okinawa airport. Neither occurrence is a plot point.
 * Trope Namers: Wax On, Wax Off, and formerly "Sweep the Leg".
 * What Could Have Been: Chuck Norris was offered the role of Kreese, but he didn't want martial artists to be portrayed in a bad light (he would later play himself in Sidekicks, another movie with a Miyagi-like mentor and a Kreese-like villain). What's more, Toshiro Mifune reportedly auditioned for the role of Mr. Miyagi but was not fluent in English and would have had to learn all his lines phonetically.
 * The original idea for the 3rd film was set to take place in Okinawa, chronicling the Miyagi Family History.