Learning Resources 24-Hour Number Line Clock Single Student Set lets students see that a clock is simply a circular number line, and change how they learn to tell time. Each Number Line Clock comes with a clock frame, snap-on minute and hour hands, and 2 reversible number lines 1 for hours and 1 for minutes. Simply bend the number lines into a circle, connect the ends, put them into the clock face, snap on the hands, and youve created a clock.