I’m working on several posts about the differences between the anime and manga, so here’s an easy place to start. The following 11 segments were entirely original to the anime and do not have a manga equivalent.

S1EP12 – “December 25: Goodbye, Ume-sensei” (The manga had its own Christmas chapter in volume 3.)

S2EP05 -“March 25: Congratulations, Chika”

S2EP06a -“July 30: Saeta”

S2EP09a -“August 5: No Summer Vacation”

S2EP09b – “December 3: The Wolf of Inner Shinjuku: Part II”

S3EP06a – “November 15: Height of the Sky, Shade of the Grove”

S3EP07 – “May 3~4: A Day in Seven Parts”

S3EP09a – “November 22: Seniors and Freshmen”

S3EP12 – “July 12: Three Stars x Lycopene”

S3SP01a – “June 11: Yay, Family Restaurant!”

S3SP02b -“July 30: Barbecue”