While the pop star is up for favorite male singer (along with Bruno Mars, Jay-Z and Usher), Diaz is nominated for favorite voice from an animated film for her role in Shrek Forever After.
"Well, as everyone knows, the kids know their stuff, so I'm always very flattered to be their choice for anything," Diaz tells PEOPLE exclusively. "After all these years, Fiona is very close to my heart and it's awesome to know that kids around the world love her as much as I do."
This year's ceremony – typically a favorite for celebrities and their children – will air live from Los Angeles on April 2 with Jack Black returning as host for a third time.
Miley Cyrus is nominated for three awards (favorite TV actress, favorite female singer and favorite movie actress for The Last Song). In the singing category she's up against Katy Perry, Taylor Swift and Selena Gomez.
There's a sibling rivalry of sorts brewing in the favorite TV actor category: Jonas Brothers Nick and Joe are up against brothers Dylan and Cole Sprouse.
And in case you were wondering who will kick butt as favorite butt-kicker, Robert Downey Jr. (for Iron Man 2), Will Ferrell (for Megamind), Jackie Chan (for The Karate Kid) and Steve Carell (for DDispicable Me) are in the running.
For a full list of nominees, visit Nick.com.