- May 1, 1961
- May 2, 1961
- May 3, 1961 (This strip and the 1st panel of the second following strip are used on the pages for August 26 [May 5, 1961] and November 4 [May 3, 1961] of the Dayspring Peanuts: A Year's Worth of Smiles and Blessings Desk Calendar)
- May 4, 1961 (First appearance of the "The Doctor is IN" sign on Lucy's psychiatry booth)
- May 5, 1961
- May 6, 1961
- May 7, 1961
- May 8, 1961 (This strip is adapted in the episode "School Is Out!" from the 2014 French TV series Peanuts)
- May 9, 1961
- May 10, 1961 (This strip is adapted in Race for Your Life, Charlie Brown)
- May 11, 1961 (This strip is adapted in Play It Again, Charlie Brown and in the episode "Classic" from the 2014 French TV series Peanuts)
- May 12, 1961
- May 13, 1961
- May 14, 1961 (This strip is adapted in the episode "School Is Out!" from the 2014 French TV series Peanuts)
- May 15, 1961
- May 16, 1961
- May 17, 1961
- May 18, 1961
- May 19, 1961
- May 20, 1961
- May 21, 1961
- May 22, 1961 (This strip was adapted in You're a Good Man, Charlie Brown)
- May 23, 1961 (The first appearance of Faron)
- May 24, 1961
- May 25, 1961
- May 26, 1961
- May 27, 1961
- May 28, 1961 (Rerun would zing Lucy with the same sarcastic punch line on August 5, 1998)
- May 29, 1961
- May 30, 1961
- May 31, 1961 (Sally's first speaking role)
| ← April 1961 | June 1961 → |