September 20, 1957 (Snoopy kisses Lucy for the first time.)
September 21, 1957
September 22, 1957 (Football gag for 1957. One of only two times where Charlie Brown shouts "SHE DID IT AGAIN!!" instead of Aaugh!. Last football strip where Lucy is seen pulling the ball away from the left side. This strip is adapted in the episode "Trust Me" from the 2014 French TV series Peanuts)