Writing Problem: Be the Teacher

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Think about how to explain Internet-related concepts in layman’s terms.

Academic Honesty

This course’s philosophy on academic honesty is best stated as "be reasonable." The course recognizes that interactions with classmates and others can facilitate mastery of the course’s material. However, there remains a line between enlisting the help of another and submitting the work of another. This policy characterizes both sides of that line.

The essence of all work that you submit to this course must be your own. Collaboration on problems is not permitted (unless explicitly stated otherwise) except to the extent that you may ask classmates and others for help so long as that help does not reduce to another doing your work for you. Generally speaking, when asking for help, you may show your code or writing to others, but you may not view theirs, so long as you and they respect this policy’s other constraints. Collaboration on quizzes and tests is not permitted at all. Collaboration on the final project is permitted to the extent prescribed by its specification.

Below are rules of thumb that (inexhaustively) characterize acts that the course considers reasonable and not reasonable. If in doubt as to whether some act is reasonable, do not commit it until you solicit and receive approval in writing from your instructor. If a violation of this policy is suspected and confirmed, your instructor reserves the right to impose local sanctions on top of any disciplinary outcome that may include an unsatisfactory or failing grade for work submitted or for the course itself.


  • Communicating with classmates about problems in English (or some other spoken language).

  • Discussing the course’s material with others in order to understand it better.

  • Helping a classmate identify a bug in his or her code, such as by viewing, compiling, or running his or her code, even on your own computer.

  • Incorporating snippets of code that you find online or elsewhere into your own code, provided that those snippets are not themselves solutions to assigned problems and that you cite the snippets' origins.

  • Reviewing past years' quizzes, tests, and solutions thereto.

  • Sending or showing code that you’ve written to someone, possibly a classmate, so that he or she might help you identify and fix a bug.

  • Sharing snippets of your own solutions to problems online so that others might help you identify and fix a bug or other issue.

  • Turning to the web or elsewhere for instruction beyond the course’s own, for references, and for solutions to technical difficulties, but not for outright solutions to problems or your own final project.

  • Whiteboarding solutions to problems with others using diagrams or pseudocode but not actual code.

  • Working with (and even paying) a tutor to help you with the course, provided the tutor does not do your work for you.

Not Reasonable

  • Accessing a solution to some problem prior to (re-)submitting your own.

  • Asking a classmate to see his or her solution to a problem before (re-)submitting your own.

  • Decompiling, deobfuscating, or disassembling the staff’s solutions to problems.

  • Failing to cite (as with comments) the origins of code, writing, or techniques that you discover outside of the course’s own lessons and integrate into your own work, even while respecting this policy’s other constraints.

  • Giving or showing to a classmate a solution to a problem when it is he or she, and not you, who is struggling to solve it.

  • Looking at another individual’s work during a quiz or test.

  • Paying or offering to pay an individual for work that you may submit as (part of) your own.

  • Providing or making available solutions to problems to individuals who might take this course in the future.

  • Searching for, soliciting, or viewing a quiz’s questions or answers prior to taking the quiz.

  • Searching for or soliciting outright solutions to problems online or elsewhere.

  • Splitting a problem’s workload with another individual and combining your work (unless explicitly authorized by the problem itself).

  • Submitting (after possibly modifying) the work of another individual beyond allowed snippets.

  • Submitting the same or similar work to this course that you have submitted or will submit to another.

  • Using resources during a quiz beyond those explicitly allowed in the quiz’s instructions.

  • Viewing another’s solution to a problem and basing your own solution on it.


Your work on this writing problem will be evaluated along three axes primarily.


To what extent does your submission align with the requirements of the specification?


To what extent is your submission correct and free of factual errors?


To what extent is your submission readable (i.e., thoughtfully organized, coherent, words properly spelled)?

To obtain a passing grade in this course, all students must ordinarily submit all assigned problems unless granted an exception in writing by the instructor.


You should now be familiar with all the major components of networks and how they all fit together. Take a minute to think back on everything you’ve learned. If you need a reminder, these were the topics:

  • IP addresses

  • DNS

  • DHCP

  • Routers

  • TCP/IP

  • HTTP

Remember what each does? Here’s your chance to prove it.

Open a text editor and create a file called ‘teacher’ (be sure that the file extension is either .doc, .docx, .pdf, or .txt). In no more than 1500 words[1], prepare a brief, five- to seven-minute-long speech to give to a class of 3rd graders explaining how the Internet works. You should cover each of the topics above, but avoid technical jargon - remember, you’re teaching elementary school kids! The emphasis is on what each individual component does in practicality and how they all fit together, not teaching terminology and definitions.

Don’t be afraid to get creative with your explanations and come up with new analogies and demonstration ideas you haven’t yet seen. It’s your chance to be the teacher!

How to Submit

Step 1 of 3

Go to https://github.com/submit50/USERNAME, substituting USERNAME in the URL with your own GitHub username. On the left side of the screen, click on "Branch: master". In the field that says "Find or create a branch…​", type cs50/2017/ap/teacher and click "Create branch".

Step 2 of 3

Click the button that says "Upload files". Drag your teacher.(doc, docx, pdf, txt) file into the box that says "Drag files here".

Step 3 of 3

Click the green "Commit changes" button and you’re done!

If you run into any trouble, email sysadmins@cs50.harvard.edu!

You may resubmit any problem as many times as you’d like before the deadline.

Your submission should be graded for correctness within 2 minutes, at which point your score will appear at cs50.me!

This was Be the Teacher.

1. Seriously! In the real world, projects often have specifications just like this one, and it’s frequently quite important to adhere to those specifications exactly so that you are in compliance with project scope. So keep it to 1500 words, tops!