LOS ANGELES

EARLY this month, as he drove his Prius (model year 2004, nonleather seats) down a bohemian artery of Venice, the gentrifying neighborhood where he lives, Davis Guggenheim passed a public school.

Even though it is within walking distance of his home, each day he or his wife bypasses the school while delivering their children to private school.

Mr. Guggenheim, an Oscar-winning documentarian and self-described lefty, worries that his children are growing up in a bubble. He would like to enroll them in public schools. But at this one, Westminster Avenue Elementary, only about half the students pass their state math and English tests.

“The biggest problem is a lot of families’ first language is Spanish,” Mr. Guggenheim said. “People like us have sent their kids somewhere else. So we’re part of the problem.”