Describes the history, functions, limits, and interactions of the three branches of the United States government. Cornerstones of Freedom series. Interest Level: 3-6 Reading Level: 7.0 ATOS Book Level: 7.3 AR Interest Level: MG AR Points: 1 AR Quiz: 147539EN Reading Counts Level: 6.3 Reading Counts Points: 5 Lexile Measure: 910 Guided Reading Level: W.