Encoding: ASCII & UTF-8

Summary

Materials

• Day 12 PowerPoint deck
• ASCII secret message document
• Secret Messages Key
• ASCII and Unicode Character Sets
• ASCII Chart Handout
• ASCII Homework Handout
• ASCII Homework Handout in Word

Instructional Activities and Classroom Assessments

1. Explain Encoding (5 minutes)
2. Explain ASCII (10 minutes)
3. Write your name in ASCII & Binary (10 minutes)
4. ASCII and Unicode Video (15 minutes)
5. UTF-8 Discussion (5 minutes)
6. Homework

Learning Objectives

• DAT 1-A Explain how data can be represented using bits.

Essential Knowledge

• DAT-1.A.1
• DAT-1.A.2
• DAT-1.A.5
• DAT-1.A.6 Bits are grouped to represent abstractions. These abstractions include, but are not limited to, numbers, characters, and color.
• DAT-1.A.7 The same sequence of bits may represent different types of data in different contexts.

Details

0. Before class

• Cut the strips of secret messages from the ASCII Secret Messages document.
• Find something for students to pull the message from - hat, bowl, etc.

1.Explain encoding (5 minutes)

• Explain encoding is a code for "non-numbers".

2. Explain ASCII (10 minutes)

• Explain the ASCII chart
• Convert Hi to ASCII and then to Binary

3. Write your name in ASCII and Binary (10 minutes)

• Students use the ASCII chart to write their names in ASCII and binary.
• Students compose a secret message for another person in class.
• Use the text from char code block in MakeCode to develop an ASCII decoder.

4. ASCII and Unicode video (15 minutes)

• Discuss progression to Unicode
• Play video

5. UTF-8 Discussion (5 minutes)

• Discuss UTF-8

6. Homework

• Complete the ASCII Homework assignment

7. Challenge

• Using your secret message decoder as starter code, create a decoder that will convert from ASCII to symbol or symbol to ASCII.