Monthly Archives: August 2020

Programming Options while Remote Learning (Updated)

Barring an unforeseen issue, we will enabling Linux on the chromebooks of students in AP Computer Science A and Software Engineering. APCSA students will use BlueJ and Software Engineering students will use VS Code. The rest of this post is an updated version of the original post which reflects that Chrome OS 81 and later installs Debian 10 (Buster), which resolves many of the issues previously identified.

Given the uncertainty of the structure of high school this fall, I’ve been exploring various options my students in AP Computer Science A if they are learning outside of the classroom without access to our desktops. In the classroom, APCSA students use BlueJ and GitHub throughout the year and leverage Swing and third-party frameworks (i.e., media computation). All students have chromebooks and our district works with families if they don’t have wifi at home. During eLearning and Remote Learning during this past spring semester, we used as our programming environment. This sufficed given the programming activities and labs at that point in the semester, but it wasn’t ideal. It remains an option for the fall, and I’ll expand upon it later. The options that I explored may not be a good fit for your students, but I hope others find this information helpful.

Linux and Java


  • My chromebook:
    • Acer Chromebook is x86_64 architecture
    • Version 84.0.4147.127 (Official Build) (64-bit)
  • enable Linux (Beta) via Chromebook Settings app
    • specify username
    • Disk size: 7.9 GB (can change later)
  • install OpenJDK and JFX
    • sudo apt update
    • sudo apt upgrade
    • sudo apt-get install openjdk-11-jdk
    • sudo apt-get install libopenjfx-java
    • sudo apt-get install openjfx

VS Code

Most of my Software Engineering students use VS Code. I was able to get it running on our chromebooks (Acer Chromebook with x86_64 architecture).


  • enable Linux via Chromebook Settings app
  • download VS Code
  • in the Chrome OS Files app, drag VS Code from the Downloads folder to the “Linux Files” folder.
  • Install VS Code from the Linux VM by running:
    • sudo apt install ./code_1.48.1-1597857616.deb
  • VS Code will now be available from the App Launcher
  • install Java Extension Pack in VS Code
  • configure GitHub
    • install GitHub Pull Request and Issues VS Code extension
    • set user name and email address from terminal
      • git config --global “<name>"
      • git config --global <email>
    • resolve issues authenticating
      • sudo apt install gnome-keyring
      • specify a password for the keychain
    • clone a repository


  • With BlueJ, jar files are automatically included in a project if they reside in a “+libs” folder. VS Code has a similar feature if the jar files are in a “lib” folder.
  • With BlueJ, one can directly run any static method in any class. VS Code expects a standard main method to be defined.


  • initial authorization of VS Code to use GitHub fails
    • second authorization of VS Code to use GitHub works if you copy and paste the authentication URL back into VS Code



  • GitHub accessible
  • debugger


  • more sophisticated an IDE than desired for APCSA students
  • requires enabling Linux on chromebook


APCSA students have always used BlueJ as their IDE. It was a good balance of features and simplicity as it is designed for educational settings.


  • download BlueJ
  • install BlueJ
    • sudo dpkg -i BlueJ-linux-422.deb
  • BlueJ will now be available from the App Launcher


  • nonresponsive on first launch
    • killed, relaunched, worked



  • IDE designed for education
  • debugger
  • GitHub support (integration via Team feature expects a one-to-one mapping between BlueJ projects and repositories, which is different than our model, but doable)


  • requires enabling Linux on chromebook

Students who have taken Computer Programming 1 and 2 before APCSA are familiar with as it is used extensively in those classes. As mentioned above, APCSA students used last spring during Remote Learning. However, I wanted a better experience if we use again this fall.

The GitHub and integration works best when the repository contains a single project. Historically, we have created a repository for each unit and that repository contains multiple practice programming projects and a summative lab. Forcing our repository model into requires some additional configuration.


  • GitHub Classroom now supports online IDEs (e.g.,
    • however, Classroom doesn’t support Java Swing at the moment
    • so, create the .replit file explicitly and add to the repo
    • still select as the online IDE when creating the Classroom assignment but don’t specify a language or a run command
  • example .replit file
    • language = "java_swing"
    • run = "javac -classpath ./TurtleDemo:./TurtleDemo/+libs/* ./TurtleDemo/; java -classpath ./TurtleDemo:./TurtleDemo/+libs/* TurtleDemo"
    • # specify additional run commands for each project but have them commented out
    • # run = "javac -classpath ./ClassNotes ./ClassNotes/; java -classpath ./ClassNotes SyntaxErrors"
    • [...]
    • # run = "javac -classpath ./TurtleLab:./TurtleLab/+libs/* ./TurtleLab/; java -classpath ./TurtleLab:./TurtleLab/+libs/* TurtleLab"



  • GitHub support


  • students have to edit .replit file when switching between activities
  • no debugger

While exploring these options, I realized that there is an opportunity here even if students are in class with our desktops. While the programming activities and labs are designed so that everyone can complete them during class, some students, for a variety of reasons, need time outside of class. Enabling one or more of these options would provide all students the flexibility to program on their chromebook instead of relying on a Windows/macOS/Linux computer at home or working in the classroom before school.

Software Engineering Book Clubs and Panel Discussion

One of the units during the fall semester in my Software Engineering class focuses on technology, society, and ethics. The big idea is that “Students will research, analyze, discuss, and present contemporary issues at the intersection of technology, society, and ethics”. The guiding question is “How does technology affect change from the critical context of privacy, social justice, economics, education, politics, culture, security, or warfare?”. The rationale for this unit is that technology is having a dramatic impact on every aspect of today’s society. The scope of the impact ranges from the personal to international relations. Today’s students will be tomorrow’s digital citizens who will be designing, applying, and using technological products that will affect change. We achieve these standards through book clubs in which small groups of students (3-5) read, analyze, and discuss a text. Students participate in a panel discussion as the summative assessment for this unit.

The past couple of years, students read one of the following books:

  • Algorithms to Live By: The Computer Science of Human Decisions by Brian Christian
  • Blown to Bits: Your Life, Liberty, and Happiness After the Digital Explosion by Hal Abelson, Ken Ledeen, Harry Lewis
  • The Hacked World Order: How Nations Fight, Trade, Maneuver, and Manipulate in the Digital Age by Adam Segal
  • The Monsters of Education Technology by Audrey Watters
  • The Second Machine Age: Work, Progress, and Prosperity in a Time of Brilliant Technologies by Erik Brynjolfsson and Andrew McAfee
  • Weapons of Math Destruction: How Big Data Increases Inequality and Threatens Democracy by Cathy O’Neil

I present each of the books to the class and then have them force rank their choices. I then form the groups to reflect student preferences while balancing the size of groups. This year, I’ll use my genetic algorithm.

The book groups meet weekly for six weeks in the middle of our data structures unit. This serves as a refreshing change of pace as the data structures unit is fairly intense. In the past, we’ve met in the Learning Commons for book groups which is a great space for this activity.

Inspired by a Cult of Pedagogy article featuring Marisa Thompson, the weekly discussion is structured around Thoughts, lingering Questions, and Epiphanies (TQEs). Each week the book club group collaboratively completes a document (week #1 template) to capture their discussion. This provides some accountability and serves as a great resource for the panel discussion.

The sample prompts change from week to week:

  • Week 1
    • author’s claims
    • personal or group response to the author’s claims
    • evidence (examples) that support the author’s claims
    • aha! (striking) moments while reading or discussing
  • Week 2
    • Has anyone’s personal response or beliefs changed while reading the first third of the book? If no, why not?
    • How does your personal response or beliefs align with those of the author? If yes, how have they changed? Why did they change?
  • Week 3
    • Notes on research on the author. What is their background? What is their education and profession? For whom do they work? Do they have a personal connection to the topic? For which, if any, publications do they write?
    • What are the potential biases of the author?
    • How does awareness of these potential biases affect your perspective of the author’s claims?
  • Week 4
    • Through which of the following critical contexts does the technology highlighted in your text most affect change? (privacy, social justice, economics, education, politics, culture, security, of warfare)
    • how does the technology highlighted in your text affect change from the critical context selected above?
  • Week 5
    • What question is most important to be asked in relationship to your book that has not been asked? That is, what is the question for the answer that you are most excited to share? Why this question is so important?
  • Week 6
    • students are on their own at this point…

After these six weeks of reading, analyzing, and discussing their books, students demonstrate their understanding through their participation in a panel discussion. Originally, I planned on having students write individual essays. One of our Learning Support Coaches recommended alternative assessments and suggested a panel discussion. While I was nervous about managing a panel discussion, it worked incredibly well as a summative assessment and is so much more engaging than a bunch of essays.

The structure of the panel discussion varies somewhat based on the number of students in the class. Overall, there are four panel discussions over two days of class. I set up tables for the panel and the observers in the Learning Commons and invite teachers and administrators to watch the panel discussion. Each panel is comprised of a student from each of the book groups. At times, there may need to be two students from the same book group. This ensures a variety of perspectives as each will address the prompt through from the perspective of their book. Students are expected to address the prompt from the perspective of their book and its author and not their personal opinion. This is important in that I want them to demonstrate that they can take one of their author’s claims, support it with evidence, and connect it to a novel prompt with their reasoning. In addition, students are expected to respond to their peers on the panel as this should be a discussion and not just a round robin of responses to a question. Students are allowed to have notes but are cautioned that use of these notes shouldn’t distract from the panel discussion. I collect their notes at the end of the panel, which serves as supplemental evidence of their understanding. Each student is assessed based on this rubric.

I prepare several prompts for the panel discussion, but one is almost always sufficient for a 15-20 minute panel discussion. Here are the prompts that I’ve used in the past:

  • According the author’s claims presented in your text, through the lens of education [could also be any of the other critical contexts], how do the topics presented in your texts affect change?
  • According the author’s claims presented in your text, how do the concepts presented in your text affect our perception of self identity, control of one’s destiny, and self value?
  • The topics presented in your texts are technologically advanced. According the author’s claims presented in your text, how do they affect everyday people?
  • Many of the topics raised in your text are fairly depressing. According the author’s claims presented in your text, what did you find in your text that was hopeful for the future?
  • According the author’s claims presented in your text, to what extent would your author agree that technology is headed in a positive direction?

Here are a couple of my extra prompts in case a panel gets stalled:

  • The authors of your texts raised several concerns. How did they advise individuals to respond to these issues? What is their call to action?
  • According the author’s claims presented in your text, to what extent would your author agree that the ethical questions raised in this text are subjective?

I’ve been really impressed with students on the panels the past three years. As I mentioned previously, a single prompt almost always lasts 15-20 minutes and is all that is needed for a panel. Students exceeded my expectations. They really took care of each other; if someone was struggling to make a connection, they would prompt them with a bridge to help them make a connection and give them an opportunity to speak. Clearly our Communication Arts teachers have helped these students develop these impressive skills.

For the upcoming school year and the fourth year of my Software Engineering class, I will leave most of this unit unchanged. The one change that I will make is to have students read one of two books and narrow the focus to the critical context of social justice. The district Learning Services department has generously agreed to purchase additional copies such that every student will read either Weapons of Math Destruction or Race after Technology: Abolitionist Tools for the New Jim Code by Ruha Benjamin. While I worry a bit that the more focused lens will limit the panel discussions, both of these books are so rich that I expect the panel discussions will be just as good, if not better, than in the past.

2020 Summer Reading List

I haven’t published my summer reading list in a few years. This summer, for some reason, I seemed to have more time for reading. Most of my reading centered on potential new books for the Technology, Society, and Ethics book study unit in my Software Engineering class where students analyze these texts through a lens that combines the technological, societal, and ethical perspectives. Small groups of students explore the question “How does technology affect change from the critical context of privacy, social justice, economics, education, politics, culture, security, or warfare?”. I did read a couple of books for my awesome biweekly Zoom book club.

Army of None: Autonomous Weapons and the Future of War by Paul Scharre

I’ve been wanting to read this book and evaluate it for class for a couple of years. It will fit well in the software engineering unit and provide an easier to read and analyze alternative to The Hacked World Order. It is very balanced and does an excellent job presenting the challenge of even defining autonomous weapons. Personally, I found it a bit repetitive and long for my students; so, I will probably suggest groups read a subset of the chapters.

Algorithms of Oppression: How Search Engines Reinforce Racism by Safiya Umoja Noble

This was a powerful read. This book had also been on my list for a couple of years. I read it hoping it could complement Weapons of Math Destruction with a more direct focus on racism. Dr. Noble strongly illustrates how algorithms perpetuate racism. While I found the book excellent, I fear that that complexity of the text and concepts may be too much for my students. As a warning to others, some students and especially parents may be uncomfortable with the language of some of the search examples. My search continued with…

Race After Technology: Abolitionist Tools for the New Jim Code by Ruha Benjamin

This was the book for which I was looking. It presented diverse examples of what Dr. Benjamin has coined “the New Jim Code”. In addition, it didn’t resign us all to technology perpetuating engineered inequity as it presents “these forms of resistance are what I think of as abolitionist tools for the New Jim Code.” I had the pleasure of watching Dr. Benjamin’s keynote at this summer’s CSTA conference. After all of this, and the events of this summer, I decided to focus the critical context for this year’s Software Engineering book clubs to social justice. My school district has already approved the purchase of enough copies of Race after Technology and additional copies of Weapons of Math Destruction such that every student will read and analyze one of these two books. We will then have a more focused panel discussion focused specifically on how technology affects change through the critical context of social justice.

Computer Science in K-12: An A-To-Z Handbook on Teaching Programming by Shuchi Grover

This was my surprise read of the summer. I noticed a lot of discussion about this book in my Twitter. Checking the table of contents, I was surprised how many of the authors were familiar. (Grover is the editor and author or co-author of several chapters.) This book should be required reading for all computer science education programs. As I shared on Twitter:

I started with Ch 14: Naive Conceptions of Novice Programmers by Juha Sorva in @shuchig’s book Computer Science in K-12. It captured and distilled misconceptions (preconceptions per #modphys) that I have been struggling to identify. I wish I had this book 8 years ago!

I truly wish I had this book eight years ago when I started teaching computer science. I hope to convince my computer science PLC to make this book part of our work this fall semester.

Braided Sweetgrass: Indigenous Wisdom, Scientific Knowledge, and the Teachings of Plants by Robin Wall Kimmerer

I’ve started reading this book before the start of summer. It was the book that I selected for our book club. It is a book best read one chapter at a time with sufficient time between chapters to savor each. Dr. Kimmerer’s words heal you as you read them. This book connected my childhood home (near where Dr. Kimmerer lives), science, spirituality, and my love and respect of nature. My mom gifted me a signed copy of this book with the inscription “for Geoffrey, in honor of our teachers, the plants”.

The Dispossessed by Ursula Le Guin

Since we didn’t take a long road trip this summer, which is when I usually get in a Stephenson audiobook, I was pleased when another member of our book club selected a science fiction book. A classic that is as relevant now as ever.

Streaming and Recording Online Lessons

The audience for this post is a bit more specialized than usual. This post is for teachers who will be engaged in remote learning, use macOS, and have similar requirements for streaming and recording online lessons as I.

[Updated 12aug2020: I decided to purchase Loopback. It made the audio configuration so much easier. I’ve updated these instructions to tag Loopback and Soundflower-specific information.]

Here are my requirements:

  • online lessons are useful both synchronously and asynchronously, as not every student will be able to attend lessons in real-time
  • online lessons are recorded with high quality and later uploaded to my YouTube channel
  • online lessons are streamed via Google Meet and Zoom (not sure which we will use this fall)
  • during online lessons my audio is only heard via AirPods so as not to disturb my partner who is also working from home
  • multiple video sources; specifically, the FaceTime camera on my MacBook, a screen being shared (to show slides and code), and my iPhone as an external camera to capture demonstrations and drawing on paper or a whiteboard; these can be combined (for example, when displaying my screen also display a small image of me in the corner)
  • multiple audio sources; specifically, the audio from the playing videos and the audio from my mic
  • all of this works on macOS Mojave 10.14.6 (it may or may not work on Catalina)

While this solution focuses on the hardware that I already have, various substitutions should work fine. For example, any earbud/mic device could be used instead of AirPods and an external web camera could be used instead of the iPhone. You could also do all of this on Windows, except for the iPhone hardwired as a video source. From what the kids tell me, the audio configuration is a lot easier and an alternate virtual camera is available.

At the heart of the solution for these requirements is the streaming software OBS. I first learned of OBS when students on our FIRST Robotics team used it when streaming the FIRST LEGO League Qualifying Tournament that we host.

Meeting these requirements was significantly harder than expected. After much iteration, here are the condensed steps to configure a system that meets my requirements:

  • download and install OBS
  • download and install obs-mac-virtualcam
    • In order to stream via Google Meet or Zoom the composite video produced via OBS, you need to configure the video source in Meet or Zoom as the output from OBS instead of any actual camera. The obs-mac-virtualcam creates a virtual camera that displays the output from OBS.
  • [Soundflower] download and install Soundflower
    • By default, OBS cannot record the audio when playing a YouTube video in a browser, music from iTunes, or a video in QuickTime Player. This is a common challenge for those who use OBS to stream themselves playing video games and want to stream the audio from the game.
    • I’ve had Soundflower installed for a while. I don’t remember why anymore. It solves the above challenge in that it allows you to route audio from one application to another. I’ll show below how to use it.
    • Another option is Loopback from Rouge Amoeba. It looks much more powerful and Rogue Amoeba has awesome support. It is $99. If I have audio issues this fall, I’ll probably invest in Loopback.
    • create a new Multi-Output Device
      • The Audio MIDI Setup application is in the Utilities folder.
      • Click on the “+” icon and select “Create Multi-Output Device”.
      • Configure the new Multi-Output Device to use Soundflower (2ch) and AirPods.
      • Configure AirPods as the Master Device for the new Multi-Output Device.

      Multi-Output Device Configuration

      • This multi-output device routes the audio from macOS (from video, music, etc.) to the AirPods and Soundflower. We will use this multi-output device shortly.
    • configure an Aggregate Device in Audio MIDI Setup
      • Click on the “+” icon and select “Create Aggregate Device”.
      • Configure the new Aggregate Device to use AirPods (the input one) and Soundflower (2ch).
      • Configure AirPods as the Master Device for the new Aggregate Device.

      Aggregate Device Configuration

      • This aggregate device combines the audio from the mic on the AirPods (i.e., me speaking) and the audio from Soundflower (to which we routed the macOS audio from videos). We will use this Aggregate Device shortly.
    • Configure the Sound Output and Input in the Sound System Preference
      • Select the Multi-Output Device as the Output device. At this point, the macOS audio (e.g., from videos) will be sent to the AirPods and Soundflower.

      Sound Output Configuration

      • Select the AirPods as the Input device.

      Sound Input Configuration

  • [Loopback] install Loopback
    • create a Loopback virtual device
    • add Safari, iTunes, and AirPods as input devices
    • add AirPods as a monitor
  • configure the audio and video devices in Google Meet or Zoom
    • [Soundflower] select the Aggregate Device as the microphone
      • This results in the macOS audio (e.g., from videos) and the audio from the AirPod mic to be combined and streamed.
    • [Loopback] select the Loopback device as the microphone
      • This results in the macOS audio (e.g., from videos) and the audio from the AirPod mic to be combined and streamed.
    • select the AirPods as the speaker
      • This allows me to hear the macOS audio as well as the audio from others in the Google Meet or Zoom meeting.

      Google Meet Audio Configuration

    • select the OBS Virtual Camera as the video camera
      • increase the send resolution to 720p to make it easier to read code
      • your video will look mirrored, but it won’t be for others in the meeting

      Meet Video Configuration

  • configure an iPhone as an external video camera
    • I bought this handy Square Jellyfish Metal Spring Tripod Mount to hold my phone and attach to a mini tripod that I already had.
    • Connect the iPhone to the MacBook via a lightening-USB cable. The iPhone is now a video source in all applications in that whatever is on the iPhone screen is the output sent to the Mac. The quality and latency are both excellent when hardwired.
    • The hardest part here was finding an iOS app that supported landscape orientation and didn’t have any controls on the screen. I finally found True Visage, which works great.
  • configure the audio settings in OBS
    • [Soundflower]
      • select Soundflower (2ch) as the Desktop Audio
      • select AirPods as Mic/Auxiliary Audio
      • This combination of audio sources is what is used when recording in OBS. Please note that it is not the same as what is being streamed via Google Meet, which is the Aggregate Device. Selecting the Aggregate Device as the only audio source in OBS doesn’t appear to work, which was a surprise.

      OBS Audio Configuration

  • [Loopback] select Loopback as Mic/Auxiliary Audio
    Loopback OBS configuration
  • configure the video settings in OBS
    • I specified 1920×1080 as both the Base (Canvas) Resolution and the Output (Scaled) Resolution. This resolution has a 16:9 aspect ratio and looks good in Meet and Zoom. I first tried a 16:10 aspect ratio that matched that of my display, but Meet and Zoom both cropped the video output.

    OBS Video Configuration

  • create Scenes and configure Sources in OBS
    • refer to the OBS documentation for details
    • I created four scenes:
      • present: my laptop display (to show code, slides, videos, etc.) with my face from the FaceTime camera in the lower-right corner
      • whiteboard: my iPhone connected as a video source
      • practice: a black screen with the text “time to practice” for when I don’t need or want to stream any video
      • just me: me fullscreen from the FaceTime camera

    OBS Scene

  • A couple points of clarification, I record from OBS by clicking on the “Start Recording” button. I stream via Google Meet or Zoom, not from OBS. I haven’t configured streaming via OBS and won’t click on the “Start Streaming” button.
  • I configured a few hotkeys in OBS Settings to make it easy for me to switch scenes. I’ll probably configure a bunch more once I determine what I need in practice.
  • Whew; that’s it!

I tested the audio and video quality when streaming using Google Meet and it was reasonable. The audio and video quality of the recorded video from OBS is excellent. I plan to use this setup for the upcoming semester and will update this document as I learn more and improve. If you are planning or have done something similar, please share. Best wishes to everyone this fall!