- Abraham Lincoln
The original Abe was the 16th president of the United States. He was also known as "Honest Abe", which Cleo and Abe refer to Abe as in the episode.
- Mahatma Gandhi
The original Gandhi was a Prime Minister of India and was made famous for his non-violent passive resistance against the British.
- Joan or Arc
The original Joan lead the French army against the English and she was eventually burned at the stake.
- Marilyn Monroe
Famous actress and sex goddess. She says hello to JFK in a suggestive manner.
- John Fitzgerald Kennedy
President. Womanizer. Known for his thick New England accent. When Gandhi greets JFK, he does a finger gun gesture which JFK responds by flinching (a joke of the JFK assassination).
- Julius Caesar
Roman general and dictator.
- Bay of Pigs
A failed attempt by JFK to overthrow Fidel Castro. The original JFK also probably bagged Marilyn Monroe.
- Elvis Presley
Singer. Young Elvis = lean & mean. Old Elvis = overweight alcoholic pill popper. A catch phrase for Elvis was "Thank you very much." "Elvis has left the building" was announced to obsessed fans to make them go away after a concert. Original Elvis Presley was a twin, his twin brother was a stillborn however.
- Cleopatra, Walk Like An Egyptian
Cleopatra was an ancient-Egyptian queen. She is shown walking to her locker and carrying her books in a stereotypical ancient-Egyptian fashion.
- Dolly the Sheep
The first cloned mammal was a sheep named 'Dolly'. This is presumably why Scudworth's early experimentation produced Mr. Sheepman, "the first mostly-human clone." Dolly also developed arthritis and Mr. Sheepman walks with a cane. Present-day clones have various health defects. Dolly ultimately developed lung cancer and was euthanized. I guess we know what's in Mr. Sheepman's future.
- Scud-worthy
Dr. Scudworth is presumably named after the infamous and inaccurate medium-range missile used by Saddam Hussein in "Operation Desert Storm: Part One". The missile type itself came from the Soviet Union and was given its derogatory-sounding name by NATO intelligence. I'm not sure where his first name of "Cinnamon" came from, but presumably it's meant to be a counterpoint to his last name. His middle initial of "J," is a cartoon-world standard, as with "Bullwinkle J. Moose", "Rocket J. Squirrel", "Homer J. Simpson", and "Bartholomew J. Simpson".
- The Grassy Knoll
The gang hangs out in the malt shoppe "The Grassy Knoll". When the original JFK was assassinated in Dallas TX, some people reportedly saw movement in the grassy knoll nearby and that the lone gunman of Lee Harvy Oswald in the library repository was actually only one of the "lone gunmen". Many conspiracy theories are around and the issue will probably never be fully resolved. The shoppe has a 1950s or 1960s theme. JFK was assassinated on November 22, 1963.
CH fan Sarah Lemieux points out that The Grassy Knoll shoppe features a long convertable car with a dead body hanging over the side, obviously a "tribute" to JFK.
- Monroe & Miller
Clone High fan Mr Minute points out in the camera pan at the start of the Grassy Knoll shows “Marilyn Monroe in the background sitting with Nostradamus. In the series, Nostradamus is an unattractive nerd, and yet he's sitting with one of the greatest sex goddesses of all time. Could this be a parallel to her marriage with Arthur Miller?” Maybe this is an extension of the “Miller” conspiracy that consumes Clone High.
- George Washington Carver
The original George Washington Carver was a geeky type who was interested in agriculture and developed over 300 products based on peanuts.
- Eleanor Roosevelt
President's wife. Wife to Franklin Delano Roosevelt (FDR).
- Genghis Kahn
The original Genghis Kahn was the leader of the Mongolean hordes that conquered China and much of Asia in the 13th century.
- Tesla
The chalkboard behind Gandhi at the Crisis Hotline has "Tesla Rules" written on it. Nikola Tesla (a guy) made most of the inventions that made mass electricity a practical reality in the 20th century. You may have been brainwashed into thinking that Edison was the original electricity genius, but he was actually mostly just a showman, the original abuser of the patent system, and a guy who stole all of his engineers' ideas (Tesla once worked for him), and his grandiose plans for a large-scale Direct-Current (DC) electrical system simply were not practical.
- Vincent van Gogh
Painter who cut his own ear off. Also, van Gogh's bedroom doesn't look like the usual Clone High backgrounds but instead looks like it was painted, so presumably it is modelled after an actual van Gogh painting.