Actor Jeff Conaway plays a greaser-type character. This was a warm-up for his similar role of Kenickie, several years later, in the blockbuster film Grease (1978).
Richie gets Arnold to teach him jujitsu, to defend and stand up for himself, after he is humiliated by hoodlums. Years later, Pat Morita (Arnold) would star in The Karate Kid (1984) as Keisuke Miyagi, an Okinawan handyman and martial artist who teaches teenager Daniel Larusso (Ralph Macchio) karate when he is bullied.
Ken Lerner's first of ten appearances on Happy Days.
When Fonzie calls Richie Tiny Tears, he's referring to a doll manufactured from 1950 to 1968.
Arnold reveals that his real name is Mitsuma Tokahashi.