Throughout this episode, whenever a character says "Miss Landers" (the name of Beaver's teacher) or "third grade" (Beaver's school grade) you can see by reading lips that the words are dubbed, and that the characters originally said "Miss Canfield" and "second grade".
Beginning of the second season where the show's opening is changed from the illustrated sidewalk to the boys coming down the staircase off to school.
Also, the closing changes for the first time to the boys walking home from school.
This episode was actually filmed during Season 1, but was not shown until Season 2. The product code 936A indicates it was actually filmed before several Season 1 episodes.