most sea monster movies are known to be scary, but this one wasn't. there are no monsters popping out of the water. no one dies either. this is a very safe movie and it is appropriate for little kids who don't usually get scared. some kids may get scared of the ocean, but that is a rare possibility and will most likely not happen.
When I was a little kid I loved to watch scooby-doo!!! There is nothing wrong with it for kids that are 8 and older. It might scare little kids, but that all. Scooby-Doo is the best!!!
Good movie, follows the typical SD tradition :). The monster could be scary for some kids, and usually the gang is running away from the monster, but I personally don't think it's too scary.