Winnie's brother is drafted into military service in June 1968 and sent to Vietnam. The Selective Service System of the United States began the draft lottery on December 1, 1969.
Kevin chooses clothes for the first day of school (Fall 1968) while Tommy James and the Shondells' "Crystal Blue Persuasion" plays. This record wasn't released until the following spring (1969).
When Arnold's teacher, Mrs. Ritvo, asks him if he is Wayne's brother, the boom mic drops down into the shot two times in the upper left hand side of the screen.