In the second part of NPR's California Newsroom investigation, Dirty Air, we traveled to rural Northern California. There's been a shocking increase in wildfire smoke, and unhealthy air recently in California, and it can be particularly damaging for children. Reporter: Farida Jhabvala Romero, KQED The KNP Complex Fire and Windy Fire continue to grow as they scorch parts of Sequoia National Park. Thousands of firefighters are battling challenging conditions, including steep and rugged terrain. During a contentious meeting, the San Diego Unified School District Board of Education unanimously approved a COVID-19 vaccination mandate for eligible students and staff. The plan calls for younger students to be vaccinated as well, once the vaccine is approved by the Food and Drug Administration. Learn more about your ad choices. Visit megaphone.fm/adchoices