California's most valuable asset for a flourishing future is its children. After decades of burgeoning population and economic growth, however, the state now faces a very different prospect. This report provides a summary of California's demographics based on the most recent census data, and finds that dramatic changes are under way among California's children. Growth trends have shifted and children's life circumstances have been altered in significant ways. The most salient finding is that children have been declining in number, concentrating initially under age 10 but now spreading to all those under age 18.