They walked out in California, in Maryland and in Oregon, many declaring that their young voices matter and expressing concern over the president-elect's comments about minorities and the effect he will have on their communities. Some students said they had the approval of administrators.
Some of Trump's supporters have called for the demonstrations to stop, including former New York City mayor Rudy Giuliani, who dismissed the protesters as "spoiled crybabies."
Trump has accused some of being "professional protesters," although he added in a 60 Minutes interview Sunday that he also believes some are afraid for the country's future "because they don't know me."
Los Angeles
Hundreds of students from several schools on Los Angeles' heavily Hispanic east side marched out shortly after classes began in a protest they say was organized over the weekend.
The demonstrations began at Garfield High School, the subject of the 1988 film Stand and Deliver focusing on teacher Jamie Escalante's successful college-level math programs.
Students carrying signs and shouting slogans marched toward the city's nearby Mariachi Plaza.
They were soon joined by hundreds of students from several schools, many of them shouting, "Say it loud. Say it clear. Immigration, welcome here." Some carried signs reading, "Deport Trump."
Students from several high schools rally after walking out of classes to protest the election of Donald Trump as president in downtown Los Angeles Monday, Nov. 14, 2016. (Reed Saxon/Associated Press)
Among the protesters was 16-year-old Brian Rodriguez, who said he is U.S.-born to parents from Mexico and Guatemala and was offended by Trump's criticism of Latinos.
"It hurt me inside knowing somebody from outside our race is talking bad about us," said Rodriguez, who carried a sign that read "Brown and Proud."
Rodriguez said his school's principal opened the gates and told students they could participate.
Nancy Meza, a community organizer who announced the walkout, said she helped students organize it after they reached out to her.
"It was really out of frustration of students wanting to voice their opinions," Meza said. "And wanting to feel protected."
Oakland, Calif.
Hundreds of students from about a dozen high schools in Oakland skipped classes Monday morning to demonstrate against Trump's election.
Students called on California to maintain its "sanctuary cities" status for people in the country illegally, the San Francisco Chronicle reported.
Protesters against President-elect Republican Donald Trump ring Lake Merritt's shoreline in Oakland, Calif. (Noah Berger/Reuters)
John Sasaki, a spokesman for Oakland Unified School District, said administrators want students back in class as soon as possible, but they are not telling them to stop their protests.
"We support our students' First Amendment rights," he said.
Denver
About 200 middle- and high-school students left two Denver charter schools to march to the state capitol, where they chanted and held up signs saying "Millennial voice matters" and "Make peace not war."
Police and school officials escorted the students, who attend Denver's Strive Prep Excel High School and Byers Middle School, along city streets to the capitol building to ensure their safety.
'What we believe matters, and we're not going to stop.'-NoelieQuintero, high school student
They called out "Si, se puede" Spanish for "Yes, we can" and "The people united will never be divided" as they waved their signs.
Noelie Quintero, 17, who attends Strive Prep, said they were representing Latinos, Muslims, women and others marginalized by Trump.
"We're not going anywhere we're going to continue to stand strong," she said. "Even though we're only 16- and 17-year-olds and we can't vote, our voice matters. What we believe matters, and we're not going to stop."
Portland, Ore.
Portland Public School students converge on Pioneer Courthouse Square Monday for a protest against the results of last week's presidential election. (Beth Nakamura/The Oregonian/Associated Press)
In a city that has seen some of the largest and most destructive protests, a few hundred high school students from at least four campuses walked out of class to gather in the rain in front of city hall.
College students from Reed College joined the group, who held signs saying "Students for change" and "Love trumps hate." The protesters marched across the Hawthorne Bridge, some of them climbing up it, while officers stopped traffic.
It comes after protesters smashed windows at Portland businesses and caused other vandalism recently. Daily demonstrations since Thursday have led to $1 million in damage and more than 100 arrests.
Portland Mayor Charlie Hales says violent protests aren't a productive way to create change and believes they are being used in his city as cover for "outrageous, bad, criminal behaviour."
Anti-Trump student protesters march east across the Hawthorne Bridge in Portland on Monday, Nov. 14. (Dave Killen/The Oregonian/Associated Press)
A protest organizer says activists are reaching out to their counterparts in New York, Boston, Washington, D.C., and other major cities in an effort to keep Trump from prevailing on many of his issues.
"Trump is going to be president, so we need to prepare for that," Greg McKelvey of the group Portland's Resistance said Monday.
McKelvey said they want to ensure local governments fight racial disparities in policing and help address global warming.
Silver Spring, Md.
Hundreds of high school students left campus and took to the streets to declare their opposition to Trump, while hundreds more gathered for a rally at a school football stadium.
About 800 Montgomery Blair High School students attended the rally at the stadium, and most returned to class afterward, Montgomery County Public Schools spokeswoman Gboyinde Onijala said.
The ones who left joined students from nearby Northwood High School, making up a gathering that Onijala estimated at 200 to 300, some of them chanting: "Not my president."
Police Capt. Paul Starks says the protesters were peaceful except for one bottle-throwing incident. No one was hurt.
