I'd say rather normal considering how many kids put beans up their noses and eat dirt. The turtle was a nice twist at the end. Especially when Peter wants to know if it's alive and it is unclear whether he means the turtle or his brother! Nice touch mom and dad to get a pet too big to swallow.
Fun question. I'd say "neither." I don't think what he does is normal (how many kids eat turtles?) nor is he really bad (I don't think he usually means to do anything naughty). He is very curious, a little precocious, and extremely BUSY.