We know that loops allow us to do things over and over again, but now we’re going to learn how to use loops that have extra structures built right in. These new structures will allow students to create code that is more powerful and dynamic.

Even though many people use the internet daily, not very many know how it works. In this lesson, students will pretend to flow through the internet, all the while learning about connections, URLs, IP Addresses, and the DNS.

Students consider that while they are enjoying their favorite websites they may encounter messages from other kids that can make them feel angry, hurt, sad, or fearful. They explore ways to handle cyberbullying and how to respond in the face of upsetting language online.

Students discuss all the ways they use technology for communication and explore the similarities and differences between in-person and online communication. Students then brainstorm ways to respond to cyberbullying.

For more information, please visit: [r common-sense-media-power-of-words]

In computer science, we face some big, daunting problems. Challenges such as finding large prime numbers or sequencing DNA are almost impossible to do as an individual. Adding the power of others makes these tasks manageable. This lesson will show your students how helpful teamwork can be in the industry of computer science.

Loaned to Computer Science Fundamentals by the team over at Copyright and Creativity, this lesson exists to help students understand the challenges and benefits of respecting ownership and copyright, particularly in digital environments. Students should be encouraged to respect artists’ rights as an important part of being an ethical digital citizen.

Variables are used as placeholders for values such as numbers or words. Variables allow for a lot of freedom in programming. Instead of having to type out a phrase many times or remember an obscure number, computer scientists can use variables to reference them. This lesson helps to explain what variables are and how we can use them in many different ways. The idea of variables isn't an easy concept to grasp, so we recommend allowing plenty of time for discussion at the end of the lesson.

The core idea of this lesson occurs in the unplugged activity that kicks off the lesson, in which students try to keep track of IP addresses that had been randomly assigned to each student in the class, while at the same time the teacher occasionally changes students' addresses. This leads to identifying the need for an authoritative system for name-to-address mappings, known as the Domain Name System or [v DNS].

Students then briefly experiment with a DNS protocol in the Internet Simulator. The activity is similar, in that students will have to grapple with IP addresses changing in real time and use the built in DNS protocol to resolve the issues.

The lesson ends with students doing some rapid research about DNS and some of its vulnerabilities, particularly what are known as Denial of Service Attacks.

Welcome to Computer Science Principles! The first lesson is about getting students excited about the course and connecting their own personal interests to computer science. Students are asked to share something they know a lot about and teach it to a small group. Groups make a “rapid” prototype of an innovative idea and share it. Students watch a brief video about computing innovations. The lesson ends with students logging into the Code.org CSP course web site, and answering a brief prompt about what “computer science” means to them.

In this lesson students work in groups using classroom supplies and everyday objects to develop their own systems for encoding and sending simple binary messages, messages that only have two possible values. Students will think about what can be usefully conveyed in such a simple message and build a “device” to communicate the message over some physical distance.
Then students are asked to consider how to use their binary messaging devices to send a more complex message - a message with more than two possibilities, say four, or eight, or even thousands of different messages. Students will collaborate in an iterative design process in the “maker ethos” of rapidly building and improving their “device” for sending messages.

Students will explore the properties of number systems by effectively inventing a base-3 number system using circles, triangles and squares as the symbols instead of arabic numerals. Students are asked to create rules that explain how each arrangement of symbols can be generated or predicated as an orderly, logical series. The objective is to understand that you can represent *any* number with any agreed-upon set of symbols that appear in an agreed-upon order. This is as true for circles, triangle and squares as it is for the digits 0-9, or the number systems we commonly see in computer science (binary and hexadecimal).

In this lesson, students will gain more familiarity with binary numbers. The lesson will transition away from the number systems that students created in the the circle-triangle-square activity, and begin to focus on representing numeric values using the binary number system. Though students have communicated with binary before, developing a *number system* is a little different. Previously, students mapped patterns of binary values to a small set of fixed messages. A number system is infinite, and also has rules for counting - or how to get from one value to the next.

This lesson sets the the stage for why we want to learn about how the Internet works. First students share what they currently know about how the Internet works through a KWL activity.

Then students watch a short video the introduces Vint Cerf and the Internet at high level. Students then skim a memo written to the Internet Engineering Task Force (IETF) by Vint Cerf in 2002 entitled “The Internet is for Everyone,” which calls out a series of threats to the prospect that the Internet should be an open, easily and cheaply accessible resource for everyone on the planet.

Finally we foreshadow the practice PT at the end of the unit. Many of the questions and challenges raised by Vint Cerf still apply today, and students will be asked to research and present on one for the Practice PT.

In this lesson, students explore more deeply how communication between multiple computers can work over the Internet. They do this by playing a simplified game of Battleship, in which the first game is played unplugged, in their table groups, and the second game is played using the Internet Simulator, so that multiple students can connect to each other and see each other’s messages. Students must devise a messaging protocol that makes it clear who is sending the message and who the intended recipient is.

Students then devise a *binary protocol* for playing this game which will entail developing an addressing system for players, as a well as a formal packet structure for transmitting data about the state of the game.

**NOTE**: this is a large lesson that will likely need to span 2 days of class.

This is the third of three lessons that make the connection between programming and algorithms. In this lesson students continue to work with the "Human Machine Language" to get creative designing more algorithms for playing cards. One command is added to the language from the previous lesson (SWAP) that allows positions of cards to change. With the addition of swap the challenge is to design an algorithm that will move the minimum card to the front of the list while keeping the relative order of all the other cards the same. If that is achieved some other Human Machine Language challenges are available.

This lesson will probably take two days to complete. It introduces students to algorithms that process lists of data. The students will do two unplugged activities related to algorithms and program some of them themselves in App Lab. The **for** loop is re-introduced to implement these algorithms because it’s straightforward to use to process all the elements of a list. The lesson begins with an unplugged activity in which students write an algorithm to find the minimum value in a hand of cards. Students then move to Code Studio to write programs that use loops and arrays. Students are shown how to use a **for** loop to visit every element in an array. Students use this pattern to process an array in increasingly complex ways. At the end of the progression, students will write functions which process arrays to find or alter information, including finding the minimum value - a problem they worked on in the unplugged activity. Finally, an unplugged activity has students reason about linear vs. binary search and attempt to write pseudocode for a binary search.

In this kickoff to the Data Unit, students begin thinking about how data is collected and what can be learned from it. To begin the lesson, students will take a short online quiz that supposedly determines something interesting or funny about their personality. Afterwards they will brainstorm other sources of data in the world around them, leading to a discussion of how that data is collected. This discussion motivates the introduction of the Class Data Tracker project that will run through the second half of this unit. Students will take the survey for the first time and be shown what the results will look like. To close the class, students will make predictions of what they will find when all the data has been collected in a couple weeks.

This a package of 3 lessons (including remote tasks for students) that can be used as scaffolding to beging coding in Scratch.