PORTLAND, Ore. (KOIN) — Portland Public School officials are concerned about possible student protests this week, they said in a letter to parents on Sunday.

The letter said that they are thankful last week’s walk out ended peacefully but that Portland Police have warned them “that there are some outside organizations encouraging students to participate in additional protests this week.”

The letter was sent to all middle and high school families in the district.

Dear PPS Middle and High School Families, We are thankful that this week’s student walk out was safe. While we support our students’ right to exercise their free speech, we want to notify you that our partners with the Portland Police Bureau approached us with concerns that there are some outside organizations encouraging students to participate in additional protests this week. The police are concerned about the safety of our students if they join any of these outside organizations in their demonstrations. We encourage open debate and dialogue, but in a non-violent manner. We will work to create these opportunities for our students within our schools and encourage you to discuss with your students how to exercise his or her voice in a way that is consistent with your family values and supports our efforts to create safe learning environments for all of our students. Thank you in advance for your attention to this important matter, PPS Communications

The leader of Portland’s Resistance, Gregory McKelvey, announced on Sunday that a protest with high school students will take place 4 p.m. Monday at Holladay Park.

McKelvey told KOIN-6 that PPS students had been attending his group’s protests from the beginning, and they reached out to Portland’s Resistance for help organizing the protest.

“These high school students have been with us at those marches and understand that it’s about peace love and unity and that’s one of the reasons that they wanted to partner with us,” McKelvey said.

Portland’s Resistance also expressed concern over the safety of the student protesters. McKelvey said the group wanted to lend its experience in protesting to the students to help keep them safe.

“I am concerned with everybody’s safety,” McKelvey said. “Whether that has to with being beaten or arrested by the cops or with outside agitators, but that’s one of the reasons that we’re there: to help keep everybody safe.”

The Portland Student Solidarity Protest had over 1,000 people ‘interested’ in the event on Facebook.

Last Monday, students from across the district walked out of class and met in downtown Portland. Officials with Portland Public Schools said roughly 440 students from Beaumont, Irvington, MLC, Tabor, Sunnyside, Hosford, Cleveland, Wilson, Benson and Franklin were involved.

Students either skipped school or walked out of class to participate.

Portland Police Sergeant Pete Simpson said during the walk-out protest, a number of adults infiltrated the crowd and tried to encourage the students to break the law.

“Anytime you have adults start to mix with kids in these kind of events, there’s cause for concern,” Sgt. Simpson said. “Our hope would be that anybody in these events will understand that everybody needs to follow the law, and the kids shouldn’t feel like they can do something against the law because these grownups are doing it.”

While Portland’s Resistance says it is prepared to take on a large responsibility for the safety of the students, Sgt. Simpson said parents of the students are ultimately responsible for their children’s well being, and encouraged parents to talk about what these protests entail before they actually occur.