California and Delaware are the only states with laws that encourage schools to teach labor history.
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Unions and their allies are trying to flex their muscle in state legislatures, pushing for labor history to be included in social studies curriculum and hoping a new generation of high school students will one day be well-educated union members.

But the results are instead shaping up as a reminder of the tough political landscape faced by organized labor. In six states, opponents have pushed back against demands that teachers offer lessons about the first craft unions in the 19th century, the large-scale organizing drives that powered the growth of industrial unions in the 1930s, the rise of organized labor as a political machine and other highlights of America’s union movement.