Sasha Mitchell who plays Cody Lambert actually is a black belt in Tae Kwon Do as his character is in the show.
This is the first episode of season 4, and it includes an updated theme song intro. Likely to show the progression in age, all of the kids filmed updated scenes at the amusement park. Brandon Call's (JT) is the only character to be doing the same activity as he did in the first 3 seasons, which is hitting the bell at the top of a high striker, however this time Angela Watson (Karen) and Suzanne Somers (Carol) aren't standing behind him, instead 2 female bystanders who aren't a part of the cast.
The title is taken from the martial arts action movie The Karate Kid (1984) starring Ralph Macchio and Pat Morita.