Reinforce alphabet awareness with this unique CD Card Set that combines interactive sound, full - color images and text when used with the Radius Audio Learning System. Set of 40 double - sided, write - on/wipe - off activity cards includes over 80 activities linked via custom barcode to a corresponding CD programmed to help students complete the activities and answer related questions. CD contains more than 45 minutes of audio content, including a variety of instructional activities, each of which can be completed by 1 - 4 students at a time. Cards measure 8.5" x 5". Aligned with Put Reading First and Title I of No Child Left Behind.