Mizuiro Jidai is about the life of Yuko Kawai. As the story begins, she's running a track race when she's sucked onto a different world where she can see the Earth in the sky and becomes able to see the future.
No wait. That's not right.
Mizuiro Jidai is about the life of Yuko Kawai. As the story begins, she's sitting down to eat breakfast when her parents tell her that they're getting a divorce and swapping partners with the next door neighbors.
Sorry... That's not it either.
Mizuiro Jidai is about the life of Yuko Kawai. And believe it or not, she's a normal middle school girl with normal middle school girl problems. She has no hidden magical powers. Every boy she meets doesn't fall in love with her. Her parents would even be considered normal by Southern Baptist standards. There's nothing magical, fantastic, or different at all about the world she lives in. And that's really why the series is so great.
Mizuiro Jidai means "the water-colored period" (more poetically, the blue-green or aqua years) and refers to the period in a person's life as they enter adolescence. Yuko is in her blue-green years, and as many of us did, she steps along through a lot of maturing and growing up. What happens to Yuko might have happened to us. The stories in the series show how she rises above her insecurities, has fights with her friends, and deals with those things that people deal with as they grow up. While there are many great characters in the series (particularly Hiroshi-kun), the stories are what make the series so entertaining. Even for an older crowd, there's a lot of nostalgia value in Mizuiro Jidai, and it lets one remember his or her own blue-green years.