Do your kids naturally wonder how and why plants grow? How planes fly? What makes cars travel fast? Introduce them to the nature of scientific inquiry at the North Bay Science Discovery Day. With more than 100 exhibitors engaging kids in hands-on demos and activities, kids will get a taste of what it means to ask “why?” and get a quantifiable answer. This free event happens on October 27, 10 a.m.–4 p.m., at the Sonoma County Fairgrounds in Santa Rosa. For details, go to northbayscience.org.