Unit 4 - Big Data and Privacy (Last update: October 2016)

The data rich world we live in also introduces many complex questions related to public policy, law, ethics and societal impact. In many ways this unit acts as a unit on current events. It is highly likely that there will be something related to big data, privacy and security going on in the news at any point in time. The major goals of the unit are 1) for students to develop a well-rounded and balanced view about data in the world around them and both the positive and negative effects of it and 2) to understand the basics of how and why modern encryption works.

Chapter 1: The World of Big Data and Encryption

Big Questions

  • What opportunities do large data sets provide for solving problems and creating knowledge?
  • How is cybersecurity impacting the ever-increasing number of Internet users?
  • How does cryptography work?

Enduring Understandings

  • 3.2 Computing facilitates exploration and the discovery of connections in information.
  • 3.3 There are trade offs when representing information as digital data.
  • 4.2 Algorithms can solve many but not all computational problems.
  • 6.3 Cybersecurity is an important concern for the Internet and the systems built on it.
  • 7.1 Computing enhances communication, interaction, and cognition.
  • 7.3 Computing has a global affect -- both beneficial and harmful -- on people and society.
  • 7.4 Computing innovations influence and are influenced by the economic, social, and cultural contexts in which they are designed and used.

Week 1

Lesson 1: What is Big Data?

Students are introduced to the concept of “big data,” where it comes from, what makes it “big,” and how people use big data to solve problems. Students are asked to consider the ramifications of how much of their lives are “datafied” or could be.

Teacher Links: Video | Answer Key Student Links: Activity Guide |

Lesson 2: Rapid Research - Data Innovations

Students "rapidly research" a topic of personal interest and respond to questions about about how that innovation produces, uses, or consumes data. This is good practice for the Explore Performance Task which requires a research element.

Teacher Links: Answer Key Student Links: Video | Video | Video | Activity Guide | |

Lesson 3: Identifying People With Data

Students investigate some of the world’s biggest data breaches to get a sense for how frequently data breaches happen what kinds of data is lost or stolen. Students use the Data Privacy Lab tool to investigate just how easily they could be uniquely identified with a few seemingly innocuous pieces of information.

Teacher Links: Answer Key Student Links: Web Site | Web Site | Activity Guide |

Week 2

Lesson 4: The Cost of Free

Students examine some of the economic concerns and consumer tradeoffs related to apps and websites that collect and track data about you in exchange for providing you a service free of cost.

Teacher Links: Exemplar Student Links: Video | External Article | Article | Activity Guide |

Lesson 5: Simple Encryption

Students are introduced to the need for encryption and use a widget try their hand at creating and breaking (cracking) messages encoded with substitution ciphers such as the classic alphabetic shift (Caesar cipher) and random letter substitution.

Student Links: Widget | Widget |

Week 3

Lesson 6: Encryption with Keys and Passwords

Students learn about the relationship between cryptographic keys and passwords by using a widget to experiment with the Vigenère cipher. Students experiment with what makes a good password, explore some of the “human components” of cybersecurity.

Teacher Links: Answer Key | Answer Key Student Links: Worksheet | Widget | Worksheet | Code Studio Page | Video | Resource |

Optional Lesson: Hard Problems - Traveling Salesperson Problem


Students examine a well-known computationally hard problem in computer science, the Traveling Salesperson Problem (TSP). Students solve small instances of the problem, try to formulate algorithms to solve it, and discuss why these algorithms take a long time for computers (and humans) to compute.

Teacher Links: Student Links: Worksheet

Optional Lesson: One-way Functions - The WiFi Hotspot Problem


Students explore another computationally hard problem - the “Wireless Hotspot Problem” (also know as the vertex cover or dominating sets problem) - to investigate the characteristics of a "one-way function": a problem which is easy to construct in such a way that you know the solution, but is computationally hard to solve.

Teacher Links: Answer Key | Answer Key | Student Links: Worksheet | Worksheet

Lesson 7: Public Key Cryptography

This is a big, multi-step lesson that introduces the concept of public key cryptography and how it works. Students learn how the basic mechanics of using public and private keys as well as the mathematical underpinnings (multiplication + modulo) that make it all possible.

Teacher Links: Answer Key | Teacher Guide | Teacher Guide | Teacher Demonstration Guide Student Links: Activity Guide | Activity Guide | Code Studio | Video | Handout | Resource

Lesson 8: Rapid Research - Cybercrime


Students pick a type of cyber attack or cybercrime and do some rapid research to learn more about it. The lesson is a precursor to the Practice Performance Task about Big Data and Security.

Teacher Links: Answer Key Student Links: Video Worksheet | Web Resource | Video | Activity Guide

Week 4

Lesson 9: Practice PT - Big Data and Cybersecurity Dilemmas

Students complete a small research project about a dilemma related to either: Big Data - should your online experiences be tailored? or Cybersecurity - should encryption algorithms have a back door? The project mimics a Performance Task, asking students to present their findings both in a written summary and with an audio / visual artifact they found online.

Student Links: Practice PT |

Chapter Commentary

Content and Teaching Strategies

In many ways this unit acts like a current events unit since it is highly likely that there will be something related to big data, privacy and security going on in the news at any point in time. The major goals of the unit are 1) for students to develop a well-rounded and balanced view about data in the world around them and both the positive and negative effects of it and 2) to understand the basics of how and why modern encryption works.

Most of the activities in these first two weeks call for students doing research online, using some online tools to investigate issues, as well as discussing and writing about the issues. The first week could be loosely titled “Big Data is Great!” - in which students investigate how data is being used in a field or area of personal interest. The second week could be loosely titled “Big Data is Scary” - in which students see how much data about people (including them) is collected by companies, governments and other organizations, and that we often give this data away freely in exchange for a free service.

The activities in the third week around data encryption should look and feel similar to lessons from Units 1 and 2. The general pattern is to introduce a concept through an unplugged activity or thinking prompt, and then “plug it in” by using a widget to explore the concept further. The purpose of the widgets is to allow students time to play with some of the ideas - often mathematical in nature - to get sense for how they work. In particular students should come away with a high level understanding of how asymmetric encryption works and why it makes certain things possible (sending encrypted data without a shared key) and certain things basically impossible (cracking a key).

Why do it this way? • The Role of the Teacher

Many of the lessons in this unit are designed as practice for elements of the Explore Performance Task. In particular lesson 2 “Rapid Research” is good practice for the kind of relatively quick research and writing students will have to do for the Explore PT. The goal is for students to become facile with looking up sources, reading/skimming articles for their main points, and being able to explain both sides of an argument or dilemma related to big data, security and privacy.

During this unit the teacher should remind students about the Explore PT and its various elements - and keep the focus on the PT throughout the unit since really that’s the ultimate goal. Since many of the areas of investigation are open to student choice, the teacher can help by making sure students are making appropriate choices, helping them get “unstuck”, and pushing them to think more deeply and more specifically about the kinds of things they are interested in. In particular you can always ask, how does this use data to do something innovative? Rather than trying to explain a very broad topic, find a small corner of it that you can explain and demonstrate the innovation involved.