The Sprouts of Hope, made up of seventh- and eighth-graders at The King Open School, are appearing Tuesday at the Cambridge Main Library as it acquires their book on energy efficiency, “Energy Lite.”

What are you doing with all your energy?

Six students at the King Open School are using much of theirs to make people around the country think about how the other kind — the kind that shows up on electric bills — gets used and wasted.

The seventh- and eighth-graders, who call themselves The Sprouts of Hope, made a presentation in April to remind the School Committee the pilot program they inspired was a success, and that it was time to expand it and finally end city use of Styrofoam lunch trays. Now they’ve written and illustrated a book, “Energy Lite,” to show how everyday appliances, from blenders to hair dryers, waste energy and money and ultimately damage the environment.

The Cambridge Main Library is hosting the authors at 6:30 Tuesday as it acquires “Energy Lite” for its collection.

In addition to copies of the 12-page book, the library will have on hand the same Kill A Watt meters used by the authors to show appliances’ wastefulness. Readers can bring the devices home for the kinds of tests described in the book, as seen here:

The project began with the Sprouts’ mission to reduce waste in their own homes. When they discovered the incredible amount of energy used by everyday appliances, they were determined to reveal their discoveries to the public. They decided to write a book.

They have also promoted their knowledge on energy efficiency and their book across the region through fairs, presentations and events with Jane Goodall, the famed environmentalist, and the Jane Goodall Institute, which works to protect chimpanzees and their habitats and has established community-centered conservation and development programs in Africa and around the world. Its Roots & Shoots global environmental and humanitarian youth program, which includes The Sprouts of Hope, is in 120 countries.

The students lure audiences by cooking chocolate chip cookies with an energy-expending toaster oven, then connect the meter, said Melissa Ludtke, a parent and Sprouts group leader.

Such cleverness is applauded by the organization and Goodall herself — the Sprouts’ experiences with Goodall are chronicled on their blog — and she contributed a blurb for the book’s back cover: “The Sprouts of Hope have come up with such a simple idea that can make such a very big difference.”

“The Sprouts of Hope exemplify what Jane Goodall’s Roots & Shoots is all about. They want to make a difference in our world, so they have come up with this wonderful idea and have taken action, working with others, to make it happen,” said Sally Sharp Lehman, the Goodall group’s regional director. “We hope that children all over will read ‘Energy Lite’ and learn how they can act to save energy, money and the planet all at the same time.”

The Sprouts are Eliza Klein, Eve Loftus, Maya Ludtke, Kaya Mark, Lilly Sandberg and Risa Paley-Zimble.

This post was written primarily with material from a press release.