(CNN) -- One poster said "Censoring history = No Education." Another read "We deserve to know the truth." The signs were just a few lining the streets as hundreds of students from at least seven Denver-area schools walked out of their classrooms Tuesday and Wednesday to protest a proposal by a member of the Jefferson County School Board, according to CNN affiliates KDVR and KMGH. The proposal calls for a new panel to review the schools' curricula, but that's not the part that has students and parents outraged. It is the call for a review of the Advanced Placement curriculum for U.S. history classes to ensure that teaching materials present positive aspects of U.S. history and its heritage. According to the wording of the proposal, teaching materials should "promote citizenship, patriotism ... (and) respect for authority" and not "encourage or condone civil disorder, social strife or disregard of the law."
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Hundreds of students staged a walkout of schools in the Denver area
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At issue is a school board proposal to review the U.S. history curriculum
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Students say the school board wants to avoid the negative aspects of U.S. history
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The school board president says the goal is community involvement in curriculum
The protest followed walkouts by students on Monday and a protest Friday, when at least 50 teachers called in sick, according to @placeholder.