Silverado High School students walked out of the classroom for 17 minutes Wednesday to protest gun violence, days after a warning from the Clark County School District that students who participate in an upcoming national walkout will face consequences. The walkout offered an early glimpse of what organizers hope will be a national walkout on March 14, when students nationwide plan to leave school for 17 minutes to draw attention to gun violence and gun-control legislation. But in a message to principals on Sunday, Rosanne Richards, an official in the district’s academic unit, said students do not have permission to walk out of school and attendance must be taken in every class period. “If a student chooses to walk out they will be ineligible to participate in any athletics or extracurricular activities (for that day),” the message stated. Silverado students who walked out Wednesday were marked tardy if they returned late for class and absent if they did not return, a district spokeswoman said. A second national student walkout over gun violence is scheduled for April 20, the 19th anniversary of the deadly shooting at Columbine High School in Colorado.