The screenwriter specifically wrote the two kids playing basketball scene so he could get a cameo in the film.
In the scene where Greg and James are outside of Amy's work, deciding who will go in to question her, the director, specifically made the line "heads or south Carolina" as a reference to the Governor Sanford Appalachian Trail scandal, which was on the news at the time of shooting.
The line toward the end of the film where the paramedic informs Greg his injury should be healed in "a week or two" was later changed to "a month or two" after it was revealed at test screenings that a week or two was too quick of a recovery. Rather than bring the actor back in to ADR the lines the director decided to use his voice instead.