[From MangaScreener]:

Shigeo is a high strung elementary school student living with his mother. His only concern is getting ahead in life by doing well in school. He despises his father Hanao (who is separated from them), who's an idealistic free spirit and kid at heart infatuated with the sport of baseball. Shigeo's mother forces Shigeo to take time to visit his father and so begins Shigeo's lessons that there's more to life than excelling academically (courtesy of his very childish father).

In a world that has become 70% harsh desert, the Rainbow Council of the International Peace Keeping Forces, a team of super-powered global security guardians, have a growing crisis on their hands. No. 5, one of their own and known within the council as their top marksman, has left his post and gone rogue. It's up to the other guardians to track him down--but No. 5, with his mysterious companion Matroshka, won't go down without a fight.

Collection of miscellaneous short stories.

Ping pong. Table tennis. Fast, furious. You might have seen it, even played it, but you've never seen it like this! The action centers around "Smile" Tsukimoto and "Peco" Hoshino, two high school students in the midst of adolescence and out to prove they've got what it takes in the cool, cruel world of sports.

This manga even got adapted into a live-action movie.