Director Christopher O'Brien grew up two blocks away from the the house used in the film. It was in the Lower Mayfair section of Philadelphia, Pennsylvania.
"The Delsea Cool Guy" used in the drive-in sequence was the host of a national radio show that aired on XM Satellite Radio. It was called "The Cool Guy Show" and Director Christopher O'Brien co-created the program with Rob Vanore who played both characters.
In the "Lake Arrowhead" scene, the body of water used is actually not even in California. It was shot along the Delaware River water front in Bristol, PA. Director Christopher O'Brien was contemplating flying to California to capture it, but at the last minute Associate Producer Gil Bratcher thought the location in Bristol would be perfect. It ended up being 3 miles from where O'Brien was living at the time.
Director Christopher O'Brien was considering building a fake drive-in movie theater in a local supermarket parking lot. The original plan was to build a model movie screen out of balsa wood and place it in a park. While looking for pictures of local drive-in's he realized that one was actually open and that's the place they shot the date sequence.
Composer Kevin Konyha hated Christmas music so much that Director Christopher O'Brien could hardly wait to hear his version of Silent Night for the movie. To this day he is still freaked out by it.