COLUMBUS, Ohio — They looked as if they didn’t belong.

Seven students from Columbus Alternative High School filled a pocket of space in a cavernous hall of the city’s Convention Center on Monday night. They had come for a Donald J. Trump rally, but they looked as if they would be more at home at a casting call for the television show “Fame.” The group included a boy in skinny jeans who wore a wool hat and kept the fingernails on his right hand long and manicured, a girl with the sides of her head shaven, and two other girls wearing Marvel T-shirts and granny glasses.

They came to get extra credit for a history class. They were about to become part of the lesson.

Depending on which side of the Thanksgiving table one sits on, Mr. Trump’s run for the Republican presidential nomination is either the most refreshingly apolitical candidacy in ages or a steepening descent into unvarnished demagogy.

And while Mr. Trump’s heated language on surveillance of Muslims, accepting Syrian refugees and illegal immigration is firing up his crowds, it is also drawing more protesters, resulting in physical clashes.

At recent Trump rallies, supporters have spit in protesters’ faces, tackled demonstrators in Miami, and shoved and punched a Black Lives Matter activist in Alabama. (“Maybe he should have been roughed up,” Mr. Trump said after the episode.) Mostly, he has embraced the scuffles as a new and action-packed dimension of the Donald Trump experience.