FREE. Hands-on engineering, problem-solving exercise & play using age-appropriate materials. Grades K–6. Younger siblings ages 0–5 are welcome to attend & use the library’s collection of duplo bricks. 10:30 a.m. Rohnert Park–Cotati Regional Library. 6250 Lynne Condé Way, Rohnert Park. Register: tinyurl.com/4b8r9pyt.