CS 107A: Problem-solving Lab for CS 107 (Spring 2021)

How Do I Take CS 107A?

If it’s after April 2nd 5pm PT, email the CS 107A CA and do not follow the steps below.

Otherwise, do the following:

What is CS 107A?

CS 107A is the ACE course for CS 107. It is 1 unit and uses a Satisfactory/No Credit grading scheme. Grading is based on effort/participation and is lenient, as the point of CS 107A is to support students taking CS 107. If you feel like you would benefit from extra support as you take CS 107, consider applying to take the course. To enroll, you must be concurrently enrolled in CS 107, and if your application is accepted, you will be given a permission number in advance of the Add/Drop deadline to enroll in CS 107A on Axess.

The CS 107A CA is Andrew Benson. You can email him at adbenson at stanford. However, most course communication will take place on Slack. If your question is specific to CS 107 (instead of CS 107A), please use the CS 107 Ed forum (for questions about course material) or the staff email list, cs107 at cs.stanford.edu (for logistical questions).


CS 107A is offered both synchronously and asynchronously. By default, all students are assumed to take the course synchronously, which means attendance at section is required. However, in case of class or time zone conflict, students may ask the course CA for permission to take the class asynchronously. If so, students will turn in section exercises in lieu of section attendance.

Please contact the CS 107A CA if you wish to audit the course.


All course communication will take place on Slack. You may join even before enrolling in the course - see the first heading.


CS 107A is offered remotely over Zoom. All sections, office hours, etc will take place using the same Zoom meeting. You can find the meeting ID and password here. You can also access it through Canvas.

Section for Synchronous Students

Section is held on Zoom on every Tuesday and Thursday from 10am-11am PT. Synchronous students are required to attend to receive credit. Zoom tracks the number of minutes each participant is present in the call - thus, if you are not present for at least 50 of the 60 minutes of section, you will be considered absent and will not receive credit. Recordings are available on Canvas a few hours after section concludes.

In general, section consists of lecture review, practice problems (sometimes done in breakout rooms), and discussion on the solutions to the problems. In order to be prepared for section, you must keep up with lecture - section is only a supplement.

Please have your video on (if able) - you can be sure I will - so that we have more of a community feel in section. Ask questions at any time, even if you’re interrupting, whether verbally or in the chat.

I always welcome feedback on how section can be improved!

Section for Asynchronous Students

Since asynchronous students, by definition, are unable to attend section, they can receive credit for section by watching the section recording and doing the in-class section exercises on their own time. Exercises should be turned in via Canvas, and are due at the end of the day after section. For example, Tuesday section exercises are due Wednesday 11:59pm PT.

CS 107 and CS 107A move through topics at a rapid pace, so late submissions are discouraged. Thus, late submissions will only receive half credit.

Exercises are graded for completion, not correctness. In order to ensure section exercises are not a burden, you may turn in whatever you were able to finish in 30 minutes of work. Since each section recording is an hour long, and exercises can be completed within 30 minutes, doing this work should take around 3 hours per week.


In order to receive a grade of S (Satisfactory), students must receive credit for N-2 sections, where N is the number of required sections. Week 1 sections are not mandatory due to flux, and not all sections near the final weeks may be made mandatory, but otherwise, all sections are considered required.

Contact the CS 107A CA if circumstances arise that would require you to miss section. At the CS 107A CA’s discretion, you may be able to receive credit in an alternate way. Contacting the CS 107A CA 24 hours BEFORE the missed section greatly boosts your chances.

Office Hours

Office hours take place on Zoom at the following times:

Additional office hours may also be added during the binary bomb and heap allocator assignments.

CS 107A generally does not make use of a queue for questions. General questions can be discussed in the main room, even if the CS 107A CA is not present. 1-on-1 questions will be discussed in a breakout room.

If you would like help outside of scheduled office hours, contact the CS 107A CA.

Other Course Elements

Mid-Quarter Check-ins

Expect to have a 10-15 minute 1-on-1 with the CS 107A CA a couple times throughout the quarter. I just want to know how you’re doing and how I can help.


Previously recorded assignment walkthrough videos are available. These do not replace reading the writeup, but may help you get started.

Midterm Review Session

A review session separate from normal course sections will be held. We will walk through practice problems released a couple days in advance, and will review course material by request.

About ACE

Additional Calculus for Engineers (ACE) is designed to provide the skills and solid foundation in mathematics, computational math in engineering, and computer science to undergraduate students interested in pursuing an engineering degree.

The goal of ACE is to increase confidence and increase content knowledge through small group interactive sessions and the academic resources (listed below) provided to students enrolled in the program.


Students who may need an academic accommodation based on the impact of a disability must initiate the request with the Office of Accessible Education (OAE). Professional staff will evaluate the request, review appropriate medical documentation, recommend reasonable accommodations, and prepare an Accommodation Letter for faculty. The letter will indicate how long it is to be in effect. Students should contact the OAE as soon as possible since timely notice is needed to coordinate accommodations. Students should also send your accommodation letter to instructors as soon as possible. (OAE phone: 723-1066, OAE URL: http://oae.stanford.edu).

Additionally, let me know what I can do to make the course more accessible to you. Accessibility of education is important to me.