Episode 26
The episode starts with Nobita breaking his teacher's vase while he was cleaning the classroom with Suneo. Suneo agreed to help Nobita cover up his crime, on the condition that he must do whatever Suneo wants. Fearing his teacher, Nobita reluctantly agreed. Along the way, Suneo and his friends taunt Nobita about the vase. Doraemon furiously takes out a tool that spies on Suneo's house, and Nobita found out that Suneo had a habit of bedwetting. Suneo's plan backfired when Nobita taunted him with his secret bedwetting habit. In the end, Suneo's friends wanted to taunt Nobita by making him do a headstand and bark like a dog, but Suneo, fearing that Nobita may uncover his secret, did the headstand.
Aired 01/05/1979EP 26 - Episode 26

Doraemon
Nobi Nobita is a 4th-grade boy in Tokyo. One day, a round, blue cat-style robot (minus ears) pops up in his desk drawer. Nobita's great-great-grandson (or something) lives in the 22nd Century, but thanks to Nobita's mistakes, the entire family is living in poverty. To rectify this, Nobita's descendent is sent Doraemon back to the past, to help prevent Nobita from making mistakes. Of course this is a difficult task since Nobita is the weakest and least intelligent child in his class. Doraemon does, however, have a 4-dimensional pocket on his front, which contains cool gadgets from the future. With these toys, Doraemon will try to help Nobita. Unfortunately, Nobita also has the bad habit of misusing Doraemon's gadgets and landing himself in yet more trouble?
(Source: AnimeNfo)