Virtualizing CS 131

As of Thursday, March 12, CS 131 will move to virtual instruction, in line with other CS department courses, to facilitate social distancing in order to slow the spread of the COVID-19 outbreak. We explain what this means for you below.

We appreciate that the move to virtual instruction is disruptive and you may feel worried about whether it will impact your ability to learn and do well in CS 131. Please be assured that the course staff will do everything in our power to ensure that you have access to the same help and resources as before, and that you do not suffer any disadvantage over the change to virtual instruction. In particular, we may make changes to assignments, grading, and material covered in order to compensate for any issues that arise due to moving to virtual instruction.


Future lectures will use Zoom and will be recorded. You can find the link the the Zoom meeting for each lecture on the schedule page.

We will continue to try to keep lectures interactive through the lecture feedback tool, and through interaction on Zoom. Please post your questions to the lecture feedback tool as before; for questions asked interactively in the lecture, use the "Raise hand" button in the Zoom participant panel to raise your hand to answer (and don't forget to unmute when you do answer).

» Panopto folder with lecture recordings (Lecture 1-14)
» Lecture videos are also linked from the schedule page as the camera icon next to each lecture.

We understand that some students may be in different time zones, and the lecture time may not be convenient for them. If so, please make sure to watch the lecture recordings. We will make them available as quickly as we can after the lecture ends.

Post-lecture quizzes will move to a weekly schedule, with a single PLQ per week that covers both lectures. We will release the PLQ by midnight (Eastern time) on Thursday, and your answers are due by midnight on Monday. The PLQ will contain four questions, two for every lecture covered.

TA & Office Hours

We will be using Zoom for virtual hours from March 12. Check out our handy Zoom guide! (Note that Zoom works best in Google Chrome (or in the standalone Zoom application), and that you'll want to choose "Computer Audio" when prompted.)

Collaborative Hours. CS 131's collaborative hours are hard to make work virtually with the restrictions we face. We still encourage you to collaborate with others (perhaps via Zoom meetings, see to work on assignments, but we will not host collaborative hours with a TA in the traditional format. Instead, TAs will host project hours with 15-minute appointments slots during the same timeslot, run via Zoom (see below).

Project TA Hours and Lab Hours. TAs will create queues on SignMeUp as usual, but the name of the queue on SignMeUp will include a Zoom Meeting ID. You should use that Meeting ID to join the TA Hours call. Joining the TA Hours call will place you into a "waiting room" – once you are up in the queue, the TA will take you out of the waiting room and can answer your question then. If you need to show code to the TA, you can use the "Share Screen" button in Zoom to do this. TAs will still enforce the usual 15-minute time limit at TA hours.

Malte's Office Hours. Malte will hold Zoom-based office hours at the usual time from 2:30-4:30pm on Tuesdays via this link. These will operate like TA hours: you will initially be in a "waiting room" until it is your turn.


Midterm quiz

Due to the cancellation of classes, our midterm quiz planned for March 17 did not take place. To preserve class time and reduce stress for everyone, we have decided to cancel the midterm and adjust the grading percentages of other grade components proportionally. The new grading breakdown is below:

  1. Projects: 48%56%;
  2. Labs: 10%12%;
  3. Mid-term: 16% → 0%;
  4. Final quiz: 16%20%;
  5. Post-lecture quizzes: 10%12%;

Assignment deadlines

We understand that it may take some time to get used to virtual instruction. Consequently, we are adapting the assignment deadlines for the rest of the semester. The schedule reflects these new deadlines.

Late hours

We will reset everyone's late hours to zero, meaning that you will have the full 72 hour budget again for the rest of the course. As before, you can only use late hours on projects.

Final quiz

The final quiz will be take-home completed during finals week. We will release the quiz at noon on Saturday, May 9. You must hand in your completed solution by noon on Tuesday, May 12. The quiz will be designed to take about three hours to complete.

You will complete your answers in a file that you pull from a GitHub repository at the start of the quiz, and push your changes to your own private GitHub repository at the end of the quiz. (Details to follow.)

We allow you to access the internet for answering the quiz, but require that you do not use it to communicate with others. Please see the details below.

During the quiz, you may access your own notes in paper or digital form. You may also use a computer or equivalent to access your own class materials, public class materials, and online reference material. Specifically:


Please push a commit with your answers to your quiz repository before the end of our original final exam slot, 12 noon on May 12. There are no extensions on this deadline: any submissions after this deadline will not be graded (we have a tight deadline for grade entry, as some students need their grades to graduate).

S/NC option

In line with the temporary academic policies for the Spring 2020 semester, students in CS 131 will have the opportunity to change their grade option between April 13 at 9am and April 17 at 5pm.

If you chose to take CS 131 with grade option S/NC, this is what it means:

  1. You must complete and hand in all assignments (projects, labs, PLQs, final quiz) by the end of the course (May 12).
  2. You must achieve a passing grade of 70% on every project and on the final quiz; and you must achieve 70% of the total credit for all labs, and 70% of the credit for all PLQs.
We will award S/NC with distinction if your course performance is equivalent to letter grade "A".