Continuity mistake: When Squints yells "no!" and the gang run towards the fence to stop Smalls, Yeah-Yeah's hat appears and disappears between shots.
Continuity mistake: When Squints is at the pool, his hair goes from flat down to sticking up, espically when he kisses Wendy.
Continuity mistake: When the gang are jumping into the pool (minus Ham) there is a life guard watching the shallow end - in one shot he is leaning foward but when Ham says "Oh sexy" he is sitting up straight.
Audio problem: When Yeah-Yeah goes over the fence, he's panting but his breathing doesn't match his mouth or shoulder movements.
Revealing mistake: When Benny jumps off the fence, it's obvious it's a stunt person doing it instead.
Continuity mistake: When Wendy sees that Squints is drowning she takes her sunglasses and whistle and throws them off the tower, but when she gets back on her tower after kicking the boys out they are back.
Continuity mistake: When Wendy is giving mouth to mouth to Squints her head is next to his chin, but when we cut back to her she is now 5 inches away from it. Her hair also moves from the left to the right. (00:37:00)
Continuity mistake: Scotty is collecting the baseball from under the bushes. The ball rolls to a stop and the name is square level. When Scotty scoops the ball up the name is now at an angle.
Other mistake: When Benny signs the autograph for the fake baseball he signs it Babe Ruthe with an 'E' on the end. This can be seen when Smalls put it back in his step dad's trophy room.
Suggested correction: He did though it's apparently supposed to happen like that as one of the boys says "Baby Ruthe?" when he's signing it and a comment is made about how bad it looks. Strange as it seems; this appears to have been done purposefully for the movie thus would not be a mistake if that's what the actor was directed to do.
Factual error: When Franklin grabs the ball and hurdles the fence, in the next shot we see the dog (a tiny bulldog) also jump the fence and chase him. No dog that small would reasonably or realistically jump a 12 ft fence, even with a very long-running start. It would be physically impossible. This was purely for comical purposes, nothing else.
Suggested correction: Unless you're talking about a deleted scene with a different dog, the "tiny bulldog" is in fact a mastiff. And the 12 foot fence is a 6 foot fence. A mastiff can definitely jump that.
Factual error: The film takes place in the summer of 1962. The scene where the boys go to the local pool to swim, in actuality this is during the civil rights movement when racial injustice against African Americans was at its peak - they would have never allowed a young black child to swim in an all white pool during this year and time.
Continuity mistake: During one attempt to retrieve the ball, the boys use a pot attached to a long piece of angle iron. When they flip the whole contraption over to grab the ball, the part of angle iron outside the fence is still facing in the original direction.