Sure you can look at the sun, the moon and the stars anytime you want, but stargazers young and old will appreciate getting a closer view with the help of a good telescope. To that end, the Peninsula Astronomical Society runs regular free public viewing nights at the Foothill College Observatory in Los Altos on Fridays and solar observing on Saturday mornings.
It's a wonderful way to open a window on the universe for young astronomers, who can glimpse Saturn's rings or peer into the craters on the moon through the observatory's 16-inch Schmidt-Cassegrain reflector. Volunteers from the astronomical society are on hand to point the scope at interesting objects in the sky and explain what you're seeing.
Foothill College Observatory: Zoom in on moon, sun - SFGate