Revealing mistake: At the end of the movie when Josh and his friend are walking down the street, a lady crosses the street in front of them. Look closely to the left of the screen. The lady is obviously behind the tree waiting for her cue because she is not seen walking toward the tree before crossing the street. (02:06:40)
Revealing mistake: The opening scene shows Josh and Billy as kids walking down their street. At the end of the film, Josh is a kid again and the two are walking on the same street. The same cars are parked there, and the same woman is crossing the street at the same place. It's obvious both scenes were shot the same day. (00:03:20 - 02:06:30)
Revealing mistake: After young Josh is granted the Zoltar wish he drops the cable. In the following shot of him walking away not only it is not next to the machine, but it runs along the concrete, revealing it is plugged somewhere offscreen.
Answer: Paul (John Heard) tells Josh that the serve has to cross the yellow line. When Josh calls the ball short, Paul is basically trying to cheat and claims he never said the ball has to cross the line. Although I'm trying to figure out what racquet sport their playing. It looks like they're playing on a handball court, but the racquet sports I know, the ball has to cross the short line (the yellow line in "Big") on the serve but you also serve from a service area where you have to stand in front of the short line, which they don't do.
Bishop73