B-1 Encoding & Decoding

B-1 Encoding and Decoding Messages

Students will learn about encoding and decoding messages using ciphers such as the Caesar cipher. They will also learn about how Google Translate uses encoding and decoding to translate words into different languages.

Do Now (5 minutes)

TEACHER GUIDANCE:

• • Google Translate allows people to use their smartphone’s camera to translate words into a different language in real time.

  • The app works by filtering out background images to help identify text, which is then classified as letters and words then translated into the new language. The background colors and font are then able to be reintegrated into the image so it looks like the original image.

  • The Google Translate app uses decoding strategies to identify the words captured by the phone’s camera then recreate them in the new language.

Mini-Lesson (5-10 minutes)

• 1. Show students this video What is Cryptography [from Khan Academy] (1:30). Ask students to share what types of information they think needs to be encoded by computers, and why it needs to be encoded.

  2. Ask students to share any codes they may know, then show them this video about the most well-known code, the Caesar cipher: The Caesar Cipher [Khan Academy] (2:35).

  3. Model how to encode and decode a message using this Caesar Cipher Exploration tool.

TEACHER GUIDANCE: You may wish to have students work together on the 6 coded messages in the activity below. Although the answer key is on the page, encourage students not to look at it until they have solved all of the 6 secret codes!

Close-Out (5 minutes)

• 1. Review how Google Translate uses encoding and decoding strategies to translate languages, but that sometimes it can run into difficulties, evidenced by one of these videos:

• • Google Translate Songs with Anne Hathaway (from The Tonight Show Starring Jimmy Fallon)

    • One of the 40+ songs from this Google Translate Sings playlist (check for appropriateness first!!!)

• 1. Discuss the following questions:

• • What are some problems Google Translate has to deal with when encoding and decoding languages?

    • Do you think some languages are harder to encode and decode than others?

TEACHER GUIDANCE: Google Translate has to deal with many problems, including metaphors, slang, and regional words and dialect when translating between languages. This is very true of song lyrics, where words are used in specific ways to create pattern, flow, and rhyme schemes, all of which will not be replicated in Google Translate.

Standards

• CSTA 2-NI-06: Apply multiple methods of encryption to model the secure transmission of information.

  • CSTA 2-NI-05: Explain how physical and digital security measures protect electronic information.

  • CSTA 2-DA-07: Represent data using multiple encoding schemes.