# Computers Unwrapped

Constructing 5x7 matrix displays like those used on NYC subways to show the train line - the A in this case.

The curriculum is divided into seven major topics: circuits, codes, information, computation, communication, storage, and control. Each topic is introduced through everyday experiences with such artifacts as emojis, calculators and supermarket bar codes, as well as control systems in the human body. These lead to hands-on activities, such as translating between binary and decimal, computing in binary, examining individual pixels displayed by cell phones, detecting and correcting errors in messages and deconstructing bar codes.

##### A. Circuits

Course 1 provides an overview of electricity, including LEDs, batteries and switches, and concludes by introducing schematic diagrams. Course 2 develops logic circuits, focusing on the OR, AND & XOR connections, and culminates in the design of adder circuits.

##### B. Codes

Course 1 begins with symbols, and then introduces codes as systems of symbols. Next, it focuses on number bases, and develops binary codes. In course 2, the focus shifts to fixed and floating point representations of large and small numbers, using the calculator to explore the limits of each representation

##### C. Information

Beginning with simple examples of one-bit messages, students learn the concept of information and how it is measured. Activities includes sorting analog and digital devices, binary searches and constructing alphanumeric display schemes. Course 2 focuses on how monochrome and color images are displayed in print and on electronic screens.

##### D. Computation

Course 1 looks at alternative algorithms for addition in decimal and binary, while course 2 focuses on signed arithmetic in both systems.

##### E. Communication

Course 1 develops the basic problem of communication, and then focuses on the use of redundancy in communication, leading to parity-based methods for detecting errors. Course 2 dissects supermarket bar codes as well as error-correcting codes

##### F. Storage

This unit begins by comparing storage and communication, introducing data storage methods in the natural world and in pre-computer technology. Course 2 looks at computer storage of emojis, images, sound and video.

##### G. Control

Beginning with control systems in the human body, this unit develops the concept of control in course 1, and then focuses on a variety of familiar technological control systems. Course 2 focuses on the societal and safety implications of control systems, using Tesla Autopilot as a major example of what can go wrong.