Our critics weigh in on local exhibits

California Academy of Sciences. "Astrobiology: Life in the Extreme": A permanent exhibition that explores the types of environments in the universe that could support life. Daily. Hands-on Science: Visitors of all ages can examine microscopic aquatic life or study adaptations of marine animals with Academy docents and interns. Wednesdays-Fridays, 4 p.m. Snake Feeding: Watch whip snakes feed off fish. Fridays, 2 p.m. free with museum admission. 875 Howard (at Fifth St.), 750-7145, www.calacademy.org.

Zeum. "Toyz": Hands-on activities teach kids about the latest in tech toys. Daily. 221 Fourth St. (at Howard), 820-3320.