- September 1, 1978
- September 2, 1978 (End of a storyline adapted in A Charlie Brown Valentine)
- September 3, 1978
- September 4, 1978
- September 5, 1978
- September 6, 1978
- September 7, 1978
- September 8, 1978
- September 9, 1978
- September 10, 1978
- September 11, 1978
- September 12, 1978
- September 13, 1978
- September 14, 1978
- September 15, 1978
- September 16, 1978
- September 17, 1978
- September 18, 1978 (This strip is adapted in She's a Good Skate, Charlie Brown)
- September 19, 1978 (This strip and the following two strips are adapted in the episode "Not Your Day" from the 2014 French TV series Peanuts)
- September 20, 1978
- September 21, 1978
- September 22, 1978 (This strip is adapted in She's a Good Skate, Charlie Brown)
- September 23, 1978
- September 24, 1978
- September 25, 1978
- September 26, 1978
- September 27, 1978
- September 28, 1978
- September 29, 1978
- September 30, 1978
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