- September 1, 1980
- September 2, 1980
- September 3, 1980
- September 4, 1980
- September 5, 1980
- September 6, 1980
- September 7, 1980
- September 8, 1980
- September 9, 1980
- September 10, 1980
- September 11, 1980 (This strip is adapted in the segment "Sally" from The Charlie Brown and Snoopy Show episode "Snoopy's Cat Fight")
- September 12, 1980
- September 13, 1980
- September 14, 1980
- September 15, 1980
- September 16, 1980 (This strip is adapted in the title segment of The Charlie Brown and Snoopy Show episode "Linus and Lucy")
- September 17, 1980
- September 18, 1980
- September 19, 1980 (This strip and the following strip are adapted in the segment "Sit" from The Charlie Brown and Snoopy Show episode "You Can't Win, Charlie Brown" and in Snoopy's Reunion)
- September 20, 1980
- September 21, 1980 (This strip is adapted in the segment "Teaching" of the 1983 The Charlie Brown and Snoopy Show episode "Snoopy's Football Career")
- September 22, 1980
- September 23, 1980
- September 24, 1980
- September 25, 1980
- September 26, 1980
- September 27, 1980
- September 28, 1980
- September 29, 1980
- September 30, 1980
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