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Secrets of the Earth

“[T]he most important thing is for people to stop thinking they can’t do anything just because they are only one individual. If everybody thought that way, planet Earth really would be doomed!” – Secrets of the Earth, p. 36.

Creator(s) Aika Tsubota
PublisherSave the Sea Committee
Publication Date1991
GenreManga, Educational, Fantasy
Environmental Issues and ThemesAcid Rain, Animals in Danger, Anthropomorphism, Deforestation, Endangered Species, Environmental Activism, Habitat Destruction, Oil Spills, Ozone Hole
Protagonists’ IdentitiesJapanese boy and Japanese girl
Protagonist’s Level of Environmental AgencyLevel 5: High Environmental Agency and Activism
Target Audience Children
Setting(s) Japan
Cover of Secrets of the Earth
Cover of Secrets of the Earth

Environmental Themes

This project was created by twelve-year-old Japanese student Aika Tsubota as a homework assignment. The almost forty-page, handmade manga begins as two sixth-grade children, Rumi and Eichi, discover a book with the same title at their city library. When Rumi opens the book, an anthropomorphized Earth leaps out of the pages. Floating above the startled children’s heads, the adorable Earth avatar announces, “I’m here to take you on a magical tour of the secrets of the Earth!” (Tsubota 7). Despite this fantastical beginning, the rest of the manga does not deliver the “magical tour” promised by the Earth. Instead, Tsubota presents a mostly realistic, nonfictional account as the anthropomorphic Earth narrates the planet’s history, teaches Rumi and Eichi about scientific processes like the water cycle, and describes urgent threats to the environment. The six-part narrative concludes with the now enlightened Rumi and Eichi offering suggestions for ways that children can help the environment and rallying their classmates to participate in their environmental activist endeavors.

The anthropomorphic Earth teaches the children about the dangers of red and blue tides in Secrets of the Earth.

Perhaps partially due to the manga’s origins as a homework project, Tsubota primarily characterizes her child characters as ignorant and passive pupils. In the manga’s educational opening sections, Secrets of the Earth presents its environmental knowledge as a compilation of facts delivered by the omnipotent Earth, not as a collaborative learning process that children can question or participate in. During these segments, the planet does frequently ask Rumi and Eichi questions, such as “Did everything make sense?” or “Do you want to learn about that next?” (Tsubota 11, 13). However, these shallow inquiries merely gauge Rumi and Eichi’s understanding of and interest in the provided environmental information. The children never actively participate in the learning process or engage in critical inquiry of their own. As a result, the manga divests Rumi and Eichi of agency by placing the responsibility for educating them about nature solely on the Earth, not on the children themselves. However, the children do gain agency in the final two chapters of the manga as they think of ways to help protect the Earth and rally other children to participate in a recycling drive.

The manga’s mixture of whimsical characters and informative scientific facts, as well as its depiction of children as active environmental advocates, contributed to its widespread circulation in the 1990s and early 2000s. A paratextual note with no author attributed precedes the primary narrative and explains that Tsubota created the manga in 1991 “to fulfill an assignment from her homeroom to somehow present environmental issues so clearly that even first-graders can understand” (n.p.). The night that she completed the project, the note continues, Tsubota suffered a fatal cerebral hemorrhage. Her parents self-published the manga for her classmates, and the nonprofit organization the Foundation for Global Peace and Environment (FGPE) later published and distributed the original Japanese version, along with translated versions in Chinese, English, and Arabic. . The article “Aika’s Legacy: A Comic Book for the Earth” claims that, as of 2000, the manga had been translated into an additional five languages, and FGPE and other environmental organizations had distributed more than 400,000 copies to children throughout the world.

A free PDF of the manga can be downloaded here.

Rumi and Eichi help their friends collect recyclables in Secrets of the Earth


Secrets of the Earth includes a mixture of paratexts produced by Tsubota and by adults. An explanatory note written by an unnamed (presumably adult) individual provides background information about Tsubota’s death and her intentions as she created the manga. Additionally, a note to the reader explains how to read manga and notes that “the original manuscripts were not painted except 3 frames in colors. So this book has been painted in colors based on these frames as Aika’s color imagination” (Tsubota 5). However, the manga does not include the name of the artist who posthumously colored the manga.

After the conclusion of the primary narrative, in a “Final Reflections” section, Tsubota reflects on the privilege that enables her to stay in school and encourages readers to get involved in environmental activism, writing, “If everybody pitches in, I know we can turn this world into a beautiful place!” (36). Finally, a letter from the SAVE THE SEA Campain Committee discusses environmental issues in Japan, including pollution and the greenhouse effect.

Additional Resources

“Aika’s Legacy: A Comic Book for the Earth.” Earth Island Journal, 22 June 2000,

Beauvais, Clémentine. “Is There a Text in This Child? Childness and the Child-Authored Text.” Children’s Literature in Education, vol. 50, no. 1, Mar. 2019, pp. 60–75.

Posted in Educational, Fiction, Manga

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