In Johnny Get Your Tutu, we learn that the only job Johnny is capable of doing is breaking rocks with his head.
Johnny(checking out his career test results): A ballerina? Well, I am graceful... and athletic... and I look good in tights!
The title of the ballet show Johnny was practicing for during Johnny Get Your Tutu was called "Swan Pond". This is a pun on the famous ballet Swan Lake.
"I Love Rootsy":
In Forest Chump, Johnny imagines how his life would be if he marries the tribe chief's daughter. The segment is called "I Love Rootsy", and is a parody of the 50s sitcom I Love Lucy.
The scenes in which Johnny is possessed during Johnny's Inferno are parodies of certain moments from the 1971 horror novel The Exorcist, by William Peter Blatty.
Forest Chump: - Title
The title of this episode is a spoof on the famous movie Forest Gump (1994), starring Tom Hanks.