Philly's school, "Fredrick Douglass High School," misspells the name of Frederick Douglass (1818 - 1895).
It is obvious that a body double for Sylvia Kristel is used during the nude scenes - Kristel's nipples are not as protuberant as those of her double, Judy Helden.
The movie is meant to take place over the summer, however when we first see Nicole she is picking oranges, which tend to ripen in December and January.
Some of the extras from the movie theater scene are re-used for the restaurant scene, most notably the short-haired elderly woman who is sitting with her husband at the movie and is visible at the bottom of the screen when we first see Philly and Nicole sitting at their table in the restaurant.
After Nicole tells Philly to close the door to her room but before she sits down on the bed, a crew member can be seen pulling something out of the way beyond the door.