The North Bay Science Discovery Day is a one-day, free community science festival to spark curiosity and wonder in children and families. The festival brings together 100-plus organizations and 10,000 attendees — supported by 70 sponsors and 150 volunteers — for youth to talk with scientists and engineers while exploring interactive exhibits, from rockets and beehives, robots and sharks, catapults and hearts, animation, animals, art, and more. Admission and parking are free, and no tickets are required. Rain or shine. Saturday, March 7, 10 a.m.–4 p.m. Sonoma County Fairgrounds, 1450 Bennett Valley Rd., Santa Rosa. For full details, visit northbayscience.com.