- May 1, 1990
- May 2, 1990
- May 3, 1990
- May 4, 1990
- May 5, 1990
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- May 7, 1990
- May 8, 1990
- May 9, 1990
- May 10, 1990
- May 11, 1990
- May 12, 1990 (Reference to Goodnight Moon)
- May 13, 1990
- May 14, 1990
- May 15, 1990
- May 16, 1990
- May 17, 1990
- May 18, 1990 (This strip is adapted in Lucy Must Be Traded, Charlie Brown)
- May 19, 1990
- May 20, 1990
- May 21, 1990
- May 22, 1990 (This strip is adapted in Get Ready for School, Charlie Brown! and in the episode "A Fascinating Friend" from the 2014 French TV series Peanuts)
- May 23, 1990
- May 24, 1990
- May 25, 1990
- May 26, 1990
- May 27, 1990
- May 28, 1990
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- May 30, 1990
- May 31, 1990