What we call "junk food" our forebears would have called amazing, in both variety and availability. My, how times have changed. In days gone by, malnourishment was a problem; today, obesity is the problem.
California has passed a law restricting the types of food and portion sizes that can be served in schools. The road to Hell is paved with good intentions, and this law seems to fit that description perfectly. Why? Well, let's see. "How can I get around the law? Let me count the ways."
This article from the SF Chronicle is rather lengthy, but it delves deeply into why and how there's no such thing as a quick fix--especially for a societal woe.