Classic Cartoons:
* Adventures of Rocky and Bullwinkle: A classic cartoon featuring the moose Rocky and the squirrel Bullwinkle, known for their wacky adventures and fight against Boris and Natasha.
* The Amazing World of Gumball: A modern animated series following the adventures of a blue cat named Gumball and his family.
* The Adventures of Tintin: A series of comics and animated films following the adventures of the intrepid reporter Tintin.
* Animaniacs: A zany cartoon featuring the Warner brothers (Yakko, Wakko, and Dot) who break out of their Warner Bros. cartoon studio and wreak havoc.
* Arthur: An animated series about an aardvark named Arthur Read and his friends.
* Avatar: The Last Airbender: A beloved fantasy series about a young boy named Aang who must master the elements to stop an evil firelord.
More Modern Cartoons:
* Adventure Time: A fantasy series about a boy named Finn and his dog Jake, who go on adventures in the Land of Ooo.
* Amphibia: A fantasy series about a young girl named Anne Boonchuy who is transported to a world of talking frogs.
* Alice's Adventures in Wonderland: A classic animated film based on the book by Lewis Carroll.
* American Dad!: An animated sitcom about a middle-class family in Virginia.
* Apple & Onion: A series about two best friends who move to the big city and find all sorts of wacky adventures.
This is just a small sampling of the many cartoons that start with the letter A. There are many other great options out there, so feel free to explore and discover your favorites!