At least 700 Jefferson County students in Denver, Colorado left classes Wednesday morning in protest of recent decisions made by the district's school board and a new proposal to change its history curriculum.

Hundreds of students from the Chatfield and Dakota Ridge high schools walked out of their classrooms around 8 a.m. They were also joined by students from Bear Creek High School and the Alameda International High School at Wednesday's protest, which garnered the largest turnout thus far, reports Fox 31 Denver.

Many students waved American flags and held signs that read, "Don't make history a mystery," while others chanted for "education without limitation!"

The demonstrations also spilled over onto Twitter under the hashtags #StandUp4Kids and #JeffcoStandUp.

"It was kind of just spur of the moment," said Ashlyn Maher, a student organizer and a senior at Chatfield high school, according to The Denver Post. "I heard one teacher was so moved by people leaving that she started to cry," she added.

Since Friday, students and teachers have been speaking out against a JeffCo Board of Education proposal to review new Advanced Placement history curriculum, which some conservatives describe as "anti-American."

The proposal calls for promoting "positive aspects" of the U.S and eliminating material that would encourage or condone "civil disorder, social strife or disregard of the law."

Tensions have also mounted over an evaluation-based system that the district voted for last week. The new teacher payout model boasts the starting teacher's salary by about $5,000 a year, and gives raises based on their performance. However, teachers who are rated as ineffective or partially effective would receive only a one percent raise, if any at all.

Jordan Gleason, a student at Columbine High School who cut class to support the cause, said, "We've really got to fight for what we believe in."

"I'm not going to lie, there are kids here (just skipping class)," said student organizer Scott Romano from Chatfield HS. "But the majority of us are out here for the right reasons."