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Students are introduced to the concept of binary coding as a language and its practical applications in digital and communication systems.This project gives students a deeper appreciation for communication systems and an understanding of how binary symbols are used to transmit information.

As technology progresses in our society, more and more everyday items are becoming digital. Engineers use the binary system in the design of many of these digital devices. binary coding communication system decimal decode digital encode encryption language receiver transmitter A familiarity with the types of engineering fields that exist, such as computer engineering, electrical engineering, human factors/human psychology engineering, chemical engineering, civil engineering and mechanical engineering, as provided in the attached Background Information for Teachers. Translate decimal to binary representation. Translate binary to decimal representation. Describe the difference between digital and analog designs. Explain how digital systems such as binary code relate to real-world applications, for example in CD-ROMs, video games, digital cameras and cellular phones. Describe how working with binary is cumbersome, error prone and difficult for humans to read. (optional) Building switchboards (binary boxes) Internet access to binary box simulation website (if binary boxes are not available) printouts of Student Worksheet If students do not have the pre-requisite knowledge, use the attached Background Information for Teachers document, which provides suggestions on ways to introduce students to engineering, communication systems and binary number systems. It includes a brief review of the different types of engineering and how we use engineered products in our everyday lives, an introduction to communication systems and engineering fields involved, an introduction to the concepts of binary language and the history of the binary number system with historic and mathematical points to make. A numbering system that uses 0 and 1 rather than 10 digits. The binary number system is the system read by most computers and other forms of technology. In analog systems, waves are used in their original form. Systems in which analog waves are converted into numbers before they are used. A form of data that expresses letters in the form of binary code. Explain to students that they will be decoding messages using special boards. Each board has its own code for different letters. With four different switches, we can have only 16 combinations (24). Each switch can be in one of two different positions: on or off. On = 1 and off = 0. Each letter has its own code, for example, on this box (hold up a box), "off, off, off, off" or "0000" lights up a light beneath the letter "A," while "1111" represents "S." Have each student take out a piece of paper and write down "0000" on the first line and "1111" on the 16th line. Since 16 possible combinations of zeros and ones can be made, have students come up with the remaining 14 combinations of zeros and ones. Explanation of boards: Once most students are finished with the patterns, explain how to use the boards. Explain that up = 1 and down = 0. After you set the switches in an on/off pattern, press "reset" and the light appears. Write down which letter corresponds to the pattern. Creating a "key." Divide the class into groups. Ideally, assign two students per box, but up to four students works. Have one student be a "scribe" and the other a "switcher." Have the scribe work from the list of combinations and tell the other student which pattern to set. Have the switcher report which light appears. Test all 16 combinations and create a "key" for that box. (Remember, each box is different.) Decoding: Once a group has all of the letters, pass out the code that goes with the box. (Since each box has only 16 letters, be sure to give the right code for the right box). Instruct the students to switch roles, so the scribe can get a turn switching. (Often, girls are relegated to the "note taker" role, so switching roles is important!) Have students use the key they just decoded to interpret the message. Give the group with the code that says they are the winners a prize. Switch: Switch boards and codes and have students decode other codes. Group Discussion: At the end of the class, collect the boards and lead a class discussion using the Investigating Questions. Be sure to stress how binary is used in many everyday forms of technology, such as computers, CD players, cellular phones and video games. Create new codes: Explain that the wires can be rearranged so that the combinations now correspond to different letters. Have students rearrange the wires and try the different combinations of 0s and 1s to come up with new keys. Have teams come up with new messages using their 16 letters, write the code for that message and give it to another group to interpret. Have teams follow the steps listed in the Binary Encoding Activity Worksheet. If binary boxes are not available to your class, simulate the activity using the Tufts Binary Box website (http://www.engineering.tufts.edu/stemteams/binarybox/STEMSrb.html). Have all students visit the website. The first page looks like Figure 1. Have the students click on the introduction, read it, and then proceed to the main activity by clicking on the black arrows. The Binary Box page looks like Figure 2. It may be helpful to have students copy the binary code onto a sheet of paper and write the letters below the numbers as they go. If not, they can use the attached worksheet. Background Information for Teachers (doc) Background Information for Teachers (pdf) Assessment Rubric (doc) Assessment Rubric (pdf) Student Worksheet & Answer Key & Quiz (doc) Student Worksheet & Answer Key & Quiz (pdf) With only four switches on the box, why couldn't we use all the letters of the alphabet? How many switches would we need to include to use all the letters? What else could we use digital systems for? (Possible answers: Video games, CD-ROMs, digital cameras and cell phones.) How long did it take you to translate the message from binary numbers to letters? How would your life be different if your CD player or cell phone took that long to decode information? What does it mean when you say your video game system is "64 bit"? How is something that is "64 bit" different from something that is "32 bit"? Evaluate student learning based on their use of the worksheets, homework and quiz See the attached Student Worksheet document; the quiz is on the last page. Gauge student learning based on journal entries in response to different questions. See the attached Assessment Rubric. Thompson, Alfred. Resources for Teaching Binary Numbers. Links to sites that have other activities to teach students about binary numbers. http://blogs.msdn.com/b/alfredth/archive/2010/04/01/resources-for-teaching-binary-numbers.aspx Past Notable Women of Computing, School of Infomatics, City University, London Contains information on pioneering women of computing. http://www.soi.city.ac.uk/~jam/chicksrock/past-women-cs.html Garlikov, Richard. The Socratic Method: Teaching by Asking Instead of by Telling A step-by-step lecture by on binary using the Socratic method. http://www.garlikov.com/Soc_Meth.html How do we talk to machines? NASA's very simple introduction to binary language. http://spaceplace.nasa.gov/binary-code2/redirected/