Fruit Picking Day/Daniel Is Big Enough to Help Dad - S1-E11
Factual error: Daniel's dad glues and screws the door bell button to Daniel's treehouse. He does not connect any wires to it or anything of the sorts, nor is there a power source to the tree house. Yet he pushes the button and the bell rings loudly. It is too small to house batteries or a speaker on its own. And the bell was electronic sounding.
Factual error: When the militia come in to shoot Woody, they're holding pump action shotguns and you hear them pump them (meaning chamber a round so it's ready to shoot). Even if we assume Malloy and Jorge did not do this, we see/hear them both pump the shotgun twice (without ever shooting in between). However, pumping the shotgun after a round has been chambered will eject the round, in the case of Malloy and Jorge an intact round, not just the shell, would be ejected. However, we never see anything be ejected.
Factual error: Dario Brando dies in 1880 (date on the gravestone) but when he was screaming at his son from his bed, Dio was reading "The Rise of Silas Lapham", which while being appropriate for his character, would be published only 5 years laters (started serialization in 1884).