High school students in Boulder, Colorado, before a global climate strike rally on 20 September 2019.

A statewide initiative pairs climate-focused coursework with community service – and is spreading to other states As a student at a high school not far from Denver’s main airport, Anthony Muñoz wondered whether the jet fuel from airplanes flying above his campus was harming living things.

An avid gardener, Muñoz partnered with a local university to create a garden on the campus of his charter school, Vista Academy, filling it with native plants that could detect ground-level ozone pollution. He also worked with climate scientists from the National Center for Atmospheric Research, a federal office in nearby Boulder, who directed Muñoz on what data to collect, what the condition of leaves reveals about air quality and why milkweed matters for monarch butterfly migration.

“One garden’s a very good data source,” said Muñoz. “Colorado’s so beautiful, and I would hate to see it wilt away.”Muñoz built the “ozone garden” for his capstone project as part of Colorado’s seal of climate literacy, a statewide initiative that pairs climate-focused coursework with hands-on community service. To earn the seal – an endorsement on high school diplomas and transcripts – students must complete at least two advanced courses that cover the Earth’s climate systems and an approved project that tackles a climate issue in their community.

Since 2024, when Colorado lawmakers approved the seal, 26 of the state’s 179 school districts have adopted it, according to Lyra Colorado, an education non-profit that advocates for the seal. Now, the model is spreading to other states. Maine adopted its own climate seal earlier this year, and California just signed into law a bill to establish the seal for graduates there. Youth coalitions have pushed for the policy in Hawaii and Minnesota, with varying success.

Proponents of the seal argue that young people must understand and combat the climate crisis, without waiting for political leaders to reach consensus on how it should be taught. They also hope the endorsement will connect students to a rapidly expanding green workforce, preparing them to work on solar grids and climate-resilient farms or in water resource management and urban heat mitigation. And, as climate change begins to alter almost every aspect of human life, the seal could offer anxious teenagers a sense of agency and ability to make some difference.

“Where we can make the most difference is often in our local community,” said Laura Schifter, a senior fellow with the Aspen Institute’s This Is Planet Ed, a climate education group. She said the seal offers students a chance to learn about the climate crisis, a topic rarely covered in depth in K-12 classrooms, and called it “a really promising policy”.

Still, the seal has faced hurdles, including tight school district budgets, concern about new burdens on schools and the federal government’s attempts to refute climate science.

The idea for the seal originated with Lyra Colorado, the non-profit in Denver that supports community-based education programs. Rural students and educators the group was working with on another climate-related project said they wanted a way to explore climate change as a reality in their daily lives, not just through a dense unit in a textbook, according to Mary Seawell, Lyra’s CEO.

A climate change protest in Denver, Colorado, on 11 October 2019.

To earn the seal, students need to complete two classes that promote “climate literacy”, or basic principles of the climate crisis, such as its causes and how to mitigate it. One of them must be a science class, such as environmental studies, biology or earth science. The other course can be in any discipline, including the humanities or fine arts. For example, this year Denver public schools will build lessons about climate change into its state-mandated civics course, Seawell said. Student projects for the seal have addressed beaver dams, building trails, snow science and forestry management.

An estimated 1,200 students have received the seal so far, said Seawell.

Funding, though, has been a challenge: state lawmakers provided less than $20,000 for the seal’s rollout. Many students fund their projects out of pocket or, like Muñoz, secure grants: he co-wrote a $1m grant proposal to the city to pay for the gardens at his school. Lyra created its own grant program to help local schools pay for teachers’ time, student projects and even graduation cords.

Muñoz, now a sophomore studying mechanical engineering at the Colorado School of Mines, said the seal allowed him to learn climate leadership skills. He’s currently vice-president of the college’s environmental club and tries to inspire his peers to take action.

“Are you going to think beyond yourself and help not only those in need but the environment, or will you sit back and wait for someone else to change the world for you?” he said.

Getting more students involved in climate action As more students like Muñoz graduate with the seal, many have started to work on climate issues at their colleges and in new states.

Rylan Neumann graduated last year from the Boulder Valley school district, enrolling that fall at the University of California, Berkeley, to study environmental economics. Almost immediately, she joined an eco-club and boarded a train to Sacramento, where she lobbied state lawmakers in support of the state’s pending climate seal bill.

“Getting more students involved in climate action and how they’ll be impacted in the future is essential,” she said. “We’re the ones growing up in this world.”

In Hawaii, a student member of the state board of education championed the endorsement for high schools on the islands. The Minnesota Youth Council, a state advisory board with representatives from middle and high schools,