Taylor Lautner
Taylor Dooley
Cayden Boyd
George Lopez
David Arquette
Kristin Davis
Jacob Davich
Sasha Pieterse
Rico Torres
Marc Musso
Taylor Lautner as Sharkboy
Taylor Dooley as Lavagirl
Cayden Boyd as Max
George Lopez as Mr. Electric/Tobor/Ice Guardian/Mr. Electricidad
David Arquette as Max's Dad
Kristin Davis as Max's Mom
Jacob Davich as Linus/Minus
Sasha Pieterse as Marissa/Ice Princess
Rico Torres as Sharkboy's Dad
Marc Musso as Classroom Kid #1
Shane Graham as Classroom Kid #2
Tiger Darrow as Classroom Kid #3
Rocket Rodriguez as Lug
Racer Rodriguez as Sharkboy, Age 7
Rebel Rodriguez as Sharkboy, Age 5