Computer Science Unplugged (AccessComputing News Feb 2009)

Richard Ladner, AccessComputing Co-PI and Co-Director

This past summer, Anna Cavender, Lindsay Yazzolino, and I led thirty blind youth ages eight to twelve in two different Computer Science Unplugged activities. The Computer Science Unplugged program introduces youth to computing concepts without the use of computers. One group of fifteen students learned about sorting in a hands-on activity using different algorithms, including insertion sort, selection sort, and bubble sort. They sorted themselves by first name, birthday, and length of cane using the different algorithms. By physically moving their bodies during the sorting process, they modeled what these algorithms do.

A second group of fifteen students learned about finite state machines by becoming a candy machine. Each student played a role: some were coins entering the slot, while others acted out the various states of the machine. For example, one person was the twenty-cent state that was activated after two dimes were inserted. They learned how events like coins entering a machine cause the active state to change. They also learned that states are like primitive forms of memory that are found in all computational processes and machines.

Both Lindsay and I had the opportunity to speak with the students' parents as a group. I described some of the newest research on accessible technology and shared the experiences of several very successful blind scientists and engineers. Lindsay described how as a child, her interest in science grew with the support of her parents and teachers. She encouraged parents to keep their expectations high for their children.

Lindsay reviewed the Computer Science Unplugged activities to assess their accessibility to children who are blind for the Junior Science Academy. If an activity was not very accessible she modified it using her own experience as a person who is blind. For more details about the program visit