There are lots of kid-friendly events this weekend and beyond.
Flax has all sorts of art classes (scroll down and see list of events at right) for the kiddos, including cartooning classes for two different age groups on Saturday.
It's Geometry Playground time at the Exploratorium, through September 6. On Saturday, explore the intertwining geometries of various folk arts at Symmetry, Topology, and Handmade History, watch short animations by Charles and Ray Eames, Al Jarnow, and Gayle Thomas, and on Sunday, meet John Edmark, Exploratorium artist-in-residence and creator of The Geometron.