Factual error: Most of the time when Eddie uses his inhaler, he uses it wrong or doesn't even spray it in his mouth.
Factual error: In 1960 young Ben, Beverly, and Bill are all taking leave of each other. Ben starts to walk away as Bill rides his bike away; Beverly muses "My heart burns there too" while looking longingly after Bill. A white 1980s-era box truck is parked down the street in the direction that Ben is heading.
Factual error: The kids are leaving a movie theater that's playing I Was a Teenage Werewolf. This film was released in June of 1957. So one, they are in 1960 and this film would not still be playing. And two, they were shown still attending school, but they would not be attending school in June during summer break.
Suggested correction: Before the rise of home video, movies had much longer theatrical lives. It was not uncommon for a film like this to be shown as a Saturday matinee years after its initial release. I personally remember a local theater showing movies from the 60s well into the 70s.
Factual error: During the scene while Georgie is running with his boat, look at the grass, and you can see that there is a good amount of sunlight. This wouldn't make sense to have a lot of sunlight during a big rainstorm. It should have been darker due the shadow of the thunderclouds.