The Work of Circle’s Curriculum was designed to introduce students to the basic concepts of the circle and to the more complex concepts of measurement – area, circumference, central angles, and arc lengths – and the calculations of such measurements.  The 5-Level Command Cards (with rainbow coloring to indicate the Level) allow for multiple lessons and activities of work.  Students begin with the parts of the circle and work their way through the measurements of area, circumference, angles, arcs, sectors and segments.