"The Hairbrush Song" was originally titled "Oh Where Is My Razor?" Mike Nawrocki, who wrote the song, was looking for his razor to shave while singing the same melody. When he pitched it to Phil Vischer, Phil thought that it was a bad idea since kids would be looking for their parents razors and could potentially hurt themselves. So hairbrush was chosen instead.
The second segment, "The Gourds Must be Crazy", is a parody of "Star Trek". The title itself is a parody of "The Gods Must be Crazy".
Originally, the characters in the silly song weren't suppose to sing their parts, except for Larry during the chorus. But when Lisa Vischer (Junior Asparagus) sang her part in the recording booth, the characters were allowed to sing.
According to Phil, Junior's bedroom has less polygons than Khalil's eyeball.
The first episode where Larry's voice is in a higher pitch. It would stay that way throughout the course of the show, though the lisp would eventually go away.