Make a colorful, bubbling lava lamp with everyday household materials. Investigate liquid density & chemical bonds in this science experiment. Kids-only, interactive science hour. For ages 6–12. $10–$12. Parking: $7. Two sessions: 11 a.m.–noon & 1–2 p.m. Environmental Discovery Center. 393 Violetti Rd., Santa Rosa. Register: secure.sonomacountyparks.org/registration.