Continuity mistake: Nick's necklace is a string looped through a ring, but sometimes the string makes only one pass through the ring and sometimes two.
Continuity mistake: When Jimmy Neutron is giving birthday presents to his mum he pulls out a necklace and some earrings from a bag. His mum only takes the necklace from him but the earrings are no longer in his hand. (00:20:10)
Continuity mistake: In the opening sequence, Jimmy uses a long string from Carl's shirt to help launch the satellite. Jimmy then launches Carl from the rocket. That same morning, Jimmy finds Carl hanging from a tree, and his shirt is intact.
Continuity mistake: When Jimmy goes to check his experiments, there is a fish tank type thing and he then checks the invisible hamsters and the girl eating plant, but when he gets to the burping soda the fish tank thing is gone.
Continuity mistake: When they are camping on the meteor, Carl states that he should have never wished on that shooting star earlier in the film when it was Jimmy who made the wish for all the parents to disappear.
Suggested correction: Carl says "WE should have never wished on that star."