Waving signs and chanting, about 400 students from King Middle School marched through downtown Portland on Friday and rallied at City Hall to draw attention to climate change and urge people to make changes today to reduce waste, pollution and carbon emissions.

“We are not here to celebrate, but to motivate,” eighth-grader Siri Pierce told the students gathered at City Hall.

“We know this will be a more serious problem in the future, so why not start fighting now?” she said to cheers. “This is our problem to solve.”

Speakers suggested immediate action, such as recycling, composting, walking or biking instead of driving, and switching out traditional light bulbs to low-energy alternatives.

“We’re the first generation to feel the effects of climate change, and the last one to be able to do anything about it,” said Satchel Butterfield, an eighth-grader. “Climate change isn’t the biggest problem. Changing it is.”

The march was timed to coincide with the United Nations climate talks in Paris, which are halfway through a two-week negotiation to fight global warming. The goal is to reach an agreement among the 195 countries taking part in the talks. Specific goals include cutting emissions and commitments to cleaner energy.

The last global climate treaty, the 1997 Kyoto Protocol, required only rich countries to reduce carbon emissions, mainly from the burning of oil, gas and coal. The United States, then the world’s largest emitter, didn’t take part. An effort in 2009 in Copenhagen to reach a global agreement from rich and poor countries alike failed.

King Middle School students have been studying climate change issues as part of their schoolwork and the march was part of the course work.

Mayor Michael Brennan gave the students a key to the city.

“I am very motivated. And you are my motivation,” he told the students, adding that the city is currently working to add solar panels to city buildings.

As the students marched from the school, cars honked in support and drivers waved. The students carried signs with environmental messages on them, and chanted: “What do we want? Climate action! When do we want it? Now!”