That, says Stephen Gardner, staff lawyer for the Center for Science in the Public Interest, is exactly the problem. In an age of soaring obesity rates among children, he argues that soda and other sugary beverages are harmful to students' health and that selling those drinks in schools sends a message that their regular consumption is perfectly fine.

In a lawsuit they plan to file in the next few months, Mr. Gardner and half a dozen other lawyers, several of them veterans of successful tobacco litigation, will seek to ban sales of sugary beverages in schools.