The Nephews - S7-E14
Factual error: Royal Wilder promises to give his sons an Indian Head nickel if they are well behaved at Almanzo's/Laura's house. The Indian Head nickel was not minted until 1913 - 30 to 40 years later.
Little House on the Prairie (1974)
1 mistake in The Nephews
Laura: I hate that Nellie Oleson.
Caroline: Laura! Don't say "hate" - don't even think "hate"! I'm sure Nellie has her good qualities somewhere.
Charles: Your ma's right, half-pint. Now on the way home, we'll try and think of some.
Trivia: Peter Billingsley of "A Christmas Story" plays Gideon in this episode. This was his television debut at age 11.