A malfunctioning ventilation unit at Cambeiro Elementary School in Las Vegas caused an evacuation Nov. 9 after several pupils experienced nausea and upset stomachs, the Las Vegas Review-Journal reported. According to the paper, the Las Vegas Fire Department's hazardous-materials team found that one of the school's HVAC units was causing an area of the school to be warmer than usual. None of the students needed to be hospitalized. According to a Fire Department spokesman, the school's air quality is fine.