Technology Marches On: Many airplanes featured in The Airport are long gone from airlines. Also, airports have vastly evolved since the game's initial release; the security is much different, for example.
Working Title: For a very long time, the series was going to be named "Junior Encyclopedias: The [Location]", and a version of The Farm actually was released under this name. It was eventually changed to Junior Field Trips, and the official game titles were changed to Let's Explore the [Location]. Farm got an updated version that reflected this, which is the one most people are familiar with.