In President Obama's first town hall meeting, his answer to the question "How do we know what makes an effective teacher?" was, by some reports, the most animated exchange. Our education guru says that the most well-meaning parents who flee public schools (and probably even well-meaning parents who have their kids in public schools) often end up unconsciously supporting bad policy decisions when they think they are doing what's best for kids. One of the best examples of this can be found in your home state of California, Eloise. California pushed through a huge statewide class-size-reduction effort in the primary grades. While it cost the state billions of dollars, the effort actually ended up diminishing teacher quality without showing any clear educational benefits. Though "conventional wisdom" still says that smaller class sizes are the most important factor in a child's educational success, the only thing the research shows to be anything close to a "silver bullet" is ensuring that children end up with a high-quality teacher for an extended time.
Finally, returning to the dilemma of the parent making the decision one child at a time: It's important to remember that there are great private schools and great public schools. So rather than worry about one type of school over the other, you should focus on identifying your child's and family's needs and do your best to find a school that meets them. The Department of Education's Guide to Choosing a School for Your Child and the Great Schools site both provide good tools and resources for deciding what factors are important to you and finding schools that meet those needs.
Do you have a real-life do-gooding dilemma? Please send it to email@example.com and Patty and Sandy will try to answer it.