- September 1, 1981
- September 2, 1981
- September 3, 1981 (This strip is adapted in the episode "School Anxiety" from the 2014 French TV series Peanuts)
- September 4, 1981
- September 5, 1981
- September 6, 1981
- September 7, 1981
- September 8, 1981
- September 9, 1981
- September 10, 1981
- September 11, 1981
- September 12, 1981
- September 13, 1981 (This strip is adapted in It's an Adventure, Charlie Brown and in the episode "Good Sports" from the 2014 French TV series Peanuts)
- September 14, 1981 (This strip and the following four strips are adapted in the title segment of The Charlie Brown and Snoopy Show episode "Linus and Lucy" and in the episode "Have a Nice Day, Linus" from the 2014 French TV series Peanuts)
- September 15, 1981
- September 16, 1981
- September 17, 1981
- September 18, 1981
- September 19, 1981
- September 20, 1981
- September 21, 1981
- September 22, 1981 (The only reference to Woodstock's cousin)
- September 23, 1981 (This strip is adapted in the book Calling All Cookies!)
- September 24, 1981
- September 25, 1981
- September 26, 1981
- September 27, 1981 (This strip is adapted in the segment "Teaching" of the 1983 The Charlie Brown and Snoopy Show episode "Snoopy's Football Career")
- September 28, 1981
- September 29, 1981
- September 30, 1981
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