Continuity mistake: When Max goes downstairs and finds the plate of cookies and the carton of milk on the counter, the carton and the cookies on the plate keep moving and changing positions during the scene. (00:09:50)
Continuity mistake: When Sharkboy is feeding the sharks at the beginning, the third shark he feeds instantly disappears underwater between shots. (00:01:25)
Continuity mistake: When Lavagirl's hair is on fire due to her anger, Sharkboy splashes her hair to put it out. Between shots her wet hair instantly dries and becomes fluffy and neat. (00:57:30)
Revealing mistake: When Sharkboy and Lavagirl are riding on Tobor's eyes to the Train of Thought, the eyeballs they ride on continue to blink shut which means they are moving forwards and back. However this doesn't affect either one of their's stance, and they just stand completely still. (00:36:30)
Continuity mistake: When Sharkboy is feeding the sharks on the dock at the beginning, there is a yellow canister behind him which disappears then reappears. (00:01:15)
Continuity mistake: When Max and his Mother walk down their garden path on his way to school, between a wideshot and closeup the position of his mothers hair completely changes. (00:13:50)
Revealing mistake: In the Milk River scene, you can see the cherry on the sound stage they are recording on.
Other mistake: Lavagirl burns everything she touches, but in some shots she touches Max's shoulders and doesn't burn him.
Continuity mistake: When Minus has the heroes captured and hanging down from wires, there is a shot where he is threatening Max and Sharkboy is nowhere to be seen. There is no wire either, so it's not like he's out of sight.
Answer: According to Taylor Lautner, the actor who played Sharkboy, he approached the role as if Sharkboy was jealous of Max because Sharkboy has a crush on Lavagirl and she pays Max lots of attention.
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