Class of Beverly Hills - S1-E1
Factual error: In this debut episode of the show, Andrea takes a bus home to "Van Nuys." After showing the bus heading to the valley on the 405 freeway, as she exits the bus, the street sign states "Gramercy Pl" which is in L.A. (not Van Nuys or the San Fernando Valley where she is supposed to be in). In addition, her house shows 548 to be the address. All addresses in Van Nuys are either four or five digits.
The Time Has Come Today - S4-E25
Factual error: The diary that Brenda finds has a Precious Moments figure on the cover. Wendy, the character who owned it, wrote it between January 1968 (an entry mentions her new year's resolution) and August 1969 (when she attended Woodstock), but the company didn't exist under that name until the late 1980s.
Answer: There was no explanation. Usually, when a show doesn't know if it's going to be picked up or not, they will use stock footage until they can spend the money on a real location.
bucade