Students staged a sit-in at a South Side high school on Thursday, protesting what they describe as harsh discipline and dress code policies under a new principal.

In videos of the sit-in and a smaller demonstration outside the school that were posted on Twitter, students at Martin Luther King Jr. College Prep in the Kenwood neighborhood are shown challenging the principal, Melanie Beatty-Sevier, about restrictions on keeping the school open in the morning and evening. At least six uniformed Chicago Police Department officers look on.

A spokesman for the police department said no arrests had been reported. Neither Beatty-Sevier nor school administrators returned a message seeking comment.

Related: Want to improve schools? Ask students. 

A spokesman for Chicago Public Schools said no disciplinary action would be taken against the students as long as the sit-in did not disrupt classroom learning.

“Empowering student voices is a priority at CPS, and the district is working closely with the school to ensure students have an opportunity to express themselves in a safe and respectful environment with minimal disruption to classroom learning,” said Chicago schools spokesman Michael Passman.

In a video posted by students on Twitter, Beatty-Sevier said that the hours were curtailed due to safety concerns.

The action one day before the district’s two-week holiday break caps a tense year at the embattled selective-enrollment high school. Rated the district’s second-highest rating, a Level 1, the school is predominantly black and reported 519 students in its enrollment count this fall.

But in the past year, the school has experienced enrollment declines, turnover in the Local School Council that helps govern it, and a change in principals, which has angered some parents.

After the previous school council voted to oust its principal last year, parents voted for a new governing body, which tried to reverse the decision and failed. Ultimately, the district hired Beatty-Sevier, who previously served as the principal at a now-closed school, Robeson High School in Englewood.

In April, parents complained to the school board about Beatty-Sevier’s appointment. By August, the critics were back, playing a recording of comments the new principal made about her strict new dress code during a school council meeting. In the recording, Beatty-Sevier said that students shouldn’t wear promiscuous clothing given the sexual abuse cases across the district. (District officials said at the time that they “strongly disagreed” with her comments).

The students’ demands shared during Thursday’s sit-in include restoring a previous policy of opening the school at 7 a.m and allowing students to stay until 6 p.m. to finish homework; staffing the media center with a certified instructor; providing more tutoring; and reversing a policy that Beatty-Sevier instituted that blocks students from re-entering the building once they leave.  

The drama has been playing out on Twitter.