Manga Seikimatsu Leader Den Takeshi!

From the moment he was born, Takeshi was born to be a leader. His first word upon birth was "leader", and his father, Hiroshi, was a "leader" among salarymen. After Hiroshi suddenly dies, Takeshi makes it his life goal to be a leader like his father, so he joins his new first grade class and hopes to become a true leader to his classmates.
This series received the 2001 Shogakukan Manga Award for children's manga.