Synchrony, Immediacy,
and Bandwidth


One of the most important decisions you will make is about when and how students will interact with you and one another—which parts of your course will be synchronous and which will be asynchronous (all courses will have some of both). Let’s look at some differences. Later we’ll examine how synchrony interacts with bandwidth and immediacy.


Real-time interactions, whether that be lectures (via Zoom), small group meetings (Zoom breakout rooms), Google Docs collaborations, team presentations, or polling. Synchronous courses have set meeting times that are advertised to students when they enroll, just like your face-to-face courses.


  • More opportunity for responsiveness and improvisation

  • More student contact

  • More real-time opportunities to dispel confusion or misunderstanding

  • More scheduled structure to support student learning


  • Student technical/scheduling challenges

  • Student attention challenges

  • Unstable internet connections

  • Challenges of managing a real-time virtual classroom


This mode of instruction relies less on real-time interactions, and more on planned activities such as lectures, assignments, group work, etc. Students typically access the materials at a time of their choosing in the timeframe you specify.


  • More temporal flexibility for instructor and students (ex: students in different time zones)

  • Potential for more cognitive engagement since students often have more time with materials (especially pre-recorded lectures)

  • Enables holistic course planning (from beginning to end)

  • Increases personalization in learning environments as students can self-pace through material

  • Potential for greater integration and sharing of applied learning, such as fieldwork (photos, interviews, research) based assignments

  • More accessible for students with limited internet bandwidth


  • Decreased real-time engagement

  • Increased potential for misunderstanding if there isn’t immediate feedback

  • Increased need to communicate often with students by providing reminders, updates and announcements

  • More front-end work to plan and set up instructional tools

  • May require more flexibility with office hours and communication practices given that there will be fewer real-time interactions

Most online courses (not to be confused with in-person courses that shifted to remote instruction in response to emergency) offered by UCSC are primarily asynchronous, but include regular synchronous class meetings, office hours, and sections (when there are Teaching Assistants). This model is closer to what is thought of as a “hybrid” course, which balances the best elements of asynchronous online learning with the hands-on classroom experience.


Now that you are considering asynchronous and synchronous instruction, this matrix (adapted from Daniel Stanford’s original) is extremely helpful. It compares immediacy and internet bandwidth, with the purpose of asking us to consider situational factors as we make course design decisions.

Immediacy is how quickly you can expect your students to respond when interacting with you and their peers. This is typically thought of as a good thing, and it is clearly woven into the fabric of face-to-face instruction. For many instructors this spring, shifting classes to synchronous Zoom-based instruction was a way to preserve immediacy in a somewhat comfortable instructional space. One of the biggest advantages of online learning, however, is that it often provides you and your students with more flexibility, as well as time to engage with instructional videos (watching and rewatching videos).

Bandwidth is just what you expect, and it’s measured by the maximum rate of data transfer of an internet connection. For those of us living at or working on a university campus, we enjoy the benefit of a very high bandwidth internet connection. For students studying from home, the same may not be true. Using high-bandwidth technologies, while gaining immediacy through them, may exclude some students from being able to fully participate. It’s important for you to consider how this may impact the success of these students, as well as their sense of belonging, in your course.

High Bandwidth/Low Immediacy (yellow)

Pre-Recorded Video

Pre-Recorded Audio

Yellow. Don’t underestimate this quadrant. Yes, it is high bandwidth, and yes it is low immediacy. However, this is where pre-recorded video or audio lectures and demonstrations are captured. With flexibility built into your course, students with low bandwidth can choose times of the day to watch or download your lectures. (We’ll talk about the tools to create pre-recorded materials later on.) We’ll come back to this in a later module, but for pre-recorded video, keep things short (no more than 15 minutes) and sequence your instruction over multiple videos that build upon each other.

High Bandwidth/High Immediacy (red)


Red. This quadrant is intentionally red. You should proceed with caution and consideration for your students' circumstances. Using Zoom for synchronous classes or office hours will provide some of the highest opportunities for immediacy in an online course, but they are the most inflexible and bandwidth-intensive activities that students can be asked to do. Zoom also poses the most challenges for accessibility and equity; live captioning is not present (unless DRC-approved with an accommodation), and some students may not have the required bandwidth, quiet home study space, or privacy to fully engage in synchronous Zoom classes. Students who do not have access to a laptop can be directed to Slug Support, which will provide one to them free of cost.

Low Bandwidth/Low Immediacy (green)

Discussion Forum



Green. The standards of instruction while teaching online or in-person. These aren’t flashy, but they are necessary and effective ways to teach and communicate with students. Mike Caulfield offers a variety of green quadrant approaches in his Dirt-Simple Online course design guide.

Low Bandwidth/High Immediacy (blue)

Shared Google Docs

Group Chat

Blue. These are standards of online teaching and learning. Collaborative documents, in particular, have a function in all courses, even if that’s just as a running list of FAQs that are compiled in a Google Doc. Keep in mind, however, that students in China may not be able to access Google platforms like Google Docs and YouTube. Slack is a popular and free software for group communications that can allow students to communicate quickly without the need for scheduling their day around a synchronous class session. is a new tool that integrates with Canvas and allows students to collaboratively annotate PDFs and websites in their web browser.

There are tradeoffs in each quadrant, and most courses combine approaches using methods from different categories. We encourage you to be imaginative in considering how each week’s assignments and activities can fit into the green quadrant. This category, which Stanford calls the “under-appreciated workhorses,” provides foundational tools (file sharing for readings and data, email, and discussion boards) that can be used to create fantastic courses. Using them also ensures that you are creating an inclusive and effective environment for learning. Finally, starting from the lower-left quadrant (green), will allow you to be more intentional and informed as you choose from the other quadrants.