A house is constantly shown to the left, across the street (the Donahue's house) from the Hecks' home. This is the set house used in Bewitched (1964). To the right of the Hecks' home is the house used for The Partridge Family (1970) .
In the episode "The Answer" Sue mentions a bunch of things she wants to do in college before getting married. Everything she mentions happens in the next season when Sue goes off to college
The original pilot episode starred Ricki Lake as Frankie Heck. Most of the cast was replaced after that production, with Atticus Shaffer (Brick) being the only actor remaining.
The fountain that appears in a few episodes is the fountain from the opening credits of Friends.
The town of Orson, Indiana, is fictional, but based on the real-life Indiana town of Jasper.