Charter school advocates lost an important legal round this week when a judge dismissed two lawsuits that sought to make the Los Angeles Unified School District hand over or share existing school sites. The judge has ordered the dispute to arbitration, which is what the district wanted. L.A. Unified also faces another legal challenge over charters. The teachers union contends that the school system has unlawfully helped a charter find space at the expense of a regular district school. They want a charter school removed from the campus of the Woodland Hills Academy. The multiple lawsuits have left hundreds of students in limbo and underscore once more the evolving interaction—and frequent conflict—between the district, traditional schools and charters.