Nonetheless, one expert is adamant that it's an investment with a priceless payoff.

David Kirp, a professor of public police at UC Berkeley and author of the book "Sandbox Investment," said the evidence is massive. "From neuroscience, from long-term evaluations that show the life-changing effects of these programs on kids, from the economists themselves showing incredible return on investments," argued Kirp.

Kirp says it may be something of a surprise to learn who is driving the movement for something that was once considered a luxury for the rich.

"It's still the case that the wealthy can buy better programs, but what's fueling this movement are middle class parents who are saying we want really good preschool for our kids. Poor parents have Head Start, rich folks can buy $30,000 a year tuition programs, Forbes Magazine reports, we need something for our kids," explained Kirp.

Despite last year's failure of a universal preschool proposition, surveys show as many as 80% of Californians want it, as does Governor Schwarzenegger.

Kirp would like to see California handle preschool the way most other states do, through legislation rather than as a ballot measure.

KCBS' Susan Leigh Taylor reports