At age 10, Levi Draheim hates math and loves reading Harry Potter books. He plays the violin but dislikes practicing. What he really enjoys is paddling a kayak or going swimming. It helps that he lives just a five-minute walk from the beach in the town of Indialantic on Florida's east coast.

"I'm the kind of kid who likes to be outside," he said.

He's also one of 21 children across America who are suing the federal government for its failure to combat climate change.

Levi, an only child who is homeschooled by his mom, is the youngest plaintiff involved in the case known as Juliana vs. the United States. He's also the only one from Florida, the state scientists say is most vulnerable to rising sea levels.

The suit, filed in federal court in Oregon in 2015 with the help of a group called Our Children's Trust, asserts that by promoting the use of fossil fuels and failing to do enough to stop climate change, government has violated the younger generation's constitutional rights to life, liberty and property. It also accuses the government of shirking its responsibility to protect essential public resources.

When the suit was first filed, the case seemed at best quixotic, and at worst a cynical ploy to use cute kids for a political end.

But the federal court system took their case seriously. A judge has set it for trial in February.

Last week, the 9th U.S. Circuit Court of Appeals in San Francisco announced it would hear oral arguments on Dec. 11 on the Trump administration's objections to proceeding to trial.

A spokesman for the Justice Department declined to comment on the case. But in court filings, the government contends that the suit is "an action that seeks wholesale changes in federal government policy based on utterly unprecedented legal theories." It also complains that the plaintiffs' request for documents from the government seeks memos going back all the way to the days of President Lyndon Johnson.

Fossil fuel companies, which had at first sought to intervene in the suit, withdrew six months ago when it became clear it was moving forward.

Whether they win or lose the suit, "these kids are forcing us to think about our legacy," said Michael P. Vandenbergh, a former Environmental Protection Agency chief of staff who is now the director of the Climate Change Research Network. "Climate change will cause harms for tens or even hundreds of generations, and they are calling us to account even if the current political dialogue has trouble focusing beyond the next week or year."

For Levi, it's an opportunity to do something about a big problem rather than just talk about it. He became a plaintiff in the suit when he was 8, and he has flown to Oregon with his family a couple of times for the preliminary court proceedings.

"I think about it a lot," he said. "Like, every day I'm thinking, 'Is this going to go through, or is it going to be stopped?'?"

When Hurricane Irma hit, he said, he saw firsthand what increased storm surges from rising seas can do. Three feet of water flooded his street. Instead of walking to the beach, he could paddle to it.

A study released earlier this year by the Grantham Research Institute on Climate Change and the Environment at the London School of Economics found that more and more people are filing climate change-related lawsuits around the globe. The number of lawsuits involving climate change has tripled since 2014, with the United States leading the way. Researchers identified 654 U.S. lawsuits — three times more than the rest of the world combined

Some suits filed in other countries have yielded concrete results. For instance, in 2015 a Pakistani lawyer's case against his government resulted in Pakistan designating action points within several ministries and creating a government commission to monitor progress.

Julia Olson founded Our Children's Trust in 2010 just to help children around the nation pursue lawsuits like this one against states and federal agencies, she said.

"What we wanted were enforceable orders" from a court, she said. The cases have also yielded documents showing that the government has known for at least 50 years that burning fossil fuels altered the climate, yet the government has continued subsidizing the industry, she said.

"The federal government controls the energy system, and it picks the winners and the losers," Olson said.

Levi said climate change is an issue he has heard his mom, Leigh-Ann Draheim, discussing with her boyfriend, photographer James Kilby, and so he read up on it.

Kilby is active with the environmental group Surfrider, said Draheim, who runs a custom kids clothing and toys sewing business. As a result, she said, "as a family we do things like beach cleanups (and) sea oat plantings."

They attend the Unitarian Universalist Church. The pastor there passed along to Draheim the information that Our Children's Trust was looking for a child from Florida to join in the suit.

"Levi was the obvious choice," she said. "He's always been interested in environmental things."

The decision was all his, according to his mother and grandfather, John Draheim.

"But we're greatly encouraging him and very proud of him," said Levi's grandfather. "He's a pretty amazing little kid, and I'm not just saying that because he's my grandson."

While he has been waiting for the case to reach its conclusion, Levi has been interviewed by the BBC and other media outlets, as well as taken part in the People's Climate March in April. He has also become friends with the other 20 kids, who are scattered from Louisiana to Hawaii. He said they frequently chat about the case over the Internet.

"It's nice knowing that there's other kids like me in the world," he said.

Times senior news researcher Caryn Baird contributed to this report. Contact Craig Pittman at craig@tampabay.com. Follow @craigtimes.