The Day of Firsts was a special 7-hour New Year's Day marathon that aired on Cartoon Network on January 1, 2005 from 12:00 PM to 7:00 PM. The marathon was meant to celebrate New Year's Day and featured very first episodes of the network's programming. Also, the marathon was hosted by Mr. Baby and Baby from Cartoon Network's Fridays.
This marathon aired again on January 1, 2007 at 7:00 AM to 10:30 PM.
- 12:00 PM - Ozzy & Drix - "Home with Hector"
- 12:30 PM - The Powerpuff Girls - "Monkey See, Doggie Do / Mommy Fearest"
- 1:00 PM - Foster's Home for Imaginary Friends - "House of Bloo's"
- 2:30 PM - Hi Hi Puffy AmiYumi - "Dis-Harmony / Collect All 5 / Ninjcompoop"
- 3:00 PM - Evil Con Carne - "Evil Con Carne / Emotional Skarr / Evil Goes Wild"
- 3:30 PM - The Grim Adventures of Billy & Mandy - "Meet the Reaper / Skeletons in the Water Closet / Opposite Day"
- 4:00 PM - Ed, Edd n Eddy - "The Ed-touchables / Nagged to Ed"
- 4:30 PM - Codename: Kids Next Door - "Operation: C.A.K.E.D. / Kenny and the Chimp in Diseasy Does It or Chimp N'Pox / No P in the OOL"
- 5:00 PM - Atomic Betty - "Atomic Roger / Toxic Talent"
- 5:30 PM - Totally Spies! - "A Thing for Musicians"
- 6:00 PM - Teen Titans - "Final Exam"
- 6:30 PM - Static Shock - "Shock to the System"