Dan Blocker played Michael Landon's brother Hoss on Landon's previous series, "Bonanza"; his son, Dirk Blocker, plays Abel Makay in this episode. Landon was very close to Dan Blocker, until Dan's death.
With rare exceptions, new characters---even when featured as main for the episode where they are introduced, and invaluable then to the regular characters---invariably never lasted on LHOTP. Here, viewers are introduced to Abel, the illiterate new pupil. He is never to be seen---nor mentioned---ever again.
The real Caroline Ingalls was a school teacher since 16 years.