Revealing mistake: During the first shot of Larry being pushed out of the car, it's blatantly a stunt double who is taller, thinner and has shorter hair than the actor.
Revealing mistake: When Nathan walks into the classroom singing, the center sliding glass door on the back bookcase is closed in the initial overhead long shot, but in the tracking shots that door has been pushed to the side, so as not to see the reflection of the camera/crew as Nathan walks up the aisle following the camera. (01:42:15)
Revealing mistake: In the parking lot of what is supposed to be Busch Stadium in St. Louis, Missouri, all the cars have Florida license plates. This happened because Ron Howard shot much of the film in Florida, not in St. Louis, Missouri.
Answer: The movie is being told in a linear timeline. You have just about all the information right! I think the one thing you are letting throw you off is your assessment of the Super Bowl. You are surmising that they had just watched the game that day, but my assessment is that they are talking about the game from months ago (bearing in mind that Larry has not been around for years and has not seen his father since the last Super Bowl). My belief is the movie takes place in May. That would add up with Kevin's next year of school being 4 months away as schools usually start in September, and the math also works out with Karen's February due date. This would also explain your concern about the weather. As for Helen's baby, it is not made clear whether or not she married Mr. Bowman, nor does it really matter for timeline purposes, but they consummated the relationship not long after the first date and she got pregnant.
jshy7979