Kiyo Nozuki and Sumire Herai are childhood friends who share a common desire to become maikos—apprentice geishas. When they join a maiko house, Kiyo is deemed unfit to be a maiko and ends up employed as a live-in cook. On the other hand, Sumire perfectly fits the maiko image and undergoes training to become one. Although disheartened by her own failure, the ever-optimistic Kiyo cooks for everyone in the house, happy to nourish and encourage them in their endeavors.

The science lessons are short omake bonus features originally present on the first two volumes of the original release. Each short lasts around two minutes, and stars super deformed versions of Noriko, Kazumi and the Coach explaining the various scientific aspects of the series. (Source: Wikipedia)

In 2029, a large scale ground sinkage occurred in the Mediterranean Sea. Chemical elements such as oxygen, carbon, gold, molybdenum, and cobalt disappeared from the earth's crust suddenly. The human population was decreased by 90% in sixty years. Researchers found out that the disappeared elements were drained into a planet Nega Earth, located in another dimension. To save the Earth, a special team called the Element Hunters is organized. All of the members are under 13 years old, because young and flexible brains are needed to access Nega Earth.

One day, Saya, an agent of the World Space Association, receives a sudden message that says a large number of asteroids are on a collision course with Earth, and it is her mission to stop them. Unfortunately, the only way to save the Earth is by having three people with extraordinary potential demonstrate a new skill on a crane game, which will create a beam of energy able to divert the asteroids. The only three people with enough potential are three high school girls—Asuka, Mirai, and Kyouko. In order to harness their energy, Saya tells them that she has scouted them as idols and has them work at an arcade where she can monitor them. She says to the girls that all successful idols are good at crane games, and that building their skills is their first step in idol training. As the girls learn new crane game techniques, they begin to doubt Saya's intentions but are nonetheless unaware that the fate of the Earth lies in their hands.