We are in the midst of the fourth wave of online education.

Known as “Cohort-Based Courses,” or CBCs, this is the first truly Internet-native form of learning. It is the first to tap into the essential nature of the Internet: that it is open-ended and interactive.

To truly understand why this is such a big deal, you have to understand the previous waves that brought us to this point.

First Wave: The MOOCs

The modern era of online education kicked off around 2008 with the launch of the first MOOCs (Massive Open Online Courses).

Pioneered by elite universities like Harvard and MIT through the EdX platform, and Stanford through Udacity, they brought courses already taught offline into an online environment. The main challenge they had to overcome was “How to get content online,” and they solved it by converting traditional course materials into digital form and delivering them over the Internet.

MOOCs launched with great fanfare and breathless press coverage. TIME dubbed 2012 “The Year of the MOOC,” pointing to examples like Introduction to Artificial Intelligence, a MOOC taught by Sebastian Thrun which had over 160,000 students enrolled.

The goal of MOOCs was to reach students who wouldn’t otherwise have access to university-level education. They seemed to offer people around the world the chance to learn on the Web for the first time.

But by 2013, the early hype of MOOCs was already fading. It started to become clear that they weren’t a silver bullet for the challenge of democratized learning. The problem was that the people who tended to successfully complete MOOCs were the same highly educated people who already had a college degree. And even then, completion rates were very low.

A comprehensive study by two MIT researchers found that between 2013 and 2018, completion rates for MOOCs steadily declined, to an average of 3% in 2018. Faced with these findings, the original MOOC pioneers shifted their focus to helping academic institutions move their programs online. In order to democratize education, it would take more than simply making educational content freely available online.

Second Wave: The Marketplaces

The second wave – the Marketplaces – began to take shape around 2010.

It was led by for-profit companies like Udemy and Skillshare, who sought to answer a new question: “How can we make money with online courses?” While large universities had large pools of funding to subsidize free, open-access courses, the industry was limited by a lack of commercialization.

The marketplaces offered a platform where anyone could create any course they wanted. For the first time, an independent instructor (not just professors with PhDs) could create a course and offer it for sale around the world without having to build their own delivery platform.

Because these instructors weren’t usually world-famous experts backed by prestigious universities, they needed exposure. The marketplaces provided exposure by centralizing the courses of thousands of instructors under one roof and driving traffic to them. The marketplace took care of finding students and referring them to the courses they might be interested in, in exchange for a percentage of the sale.

I joined Skillshare in 2013 with my first course, and was amazed to discover just how easy it was to get started. I saw other instructors teaching thousands of students and making hundreds of thousands of dollars teaching what they knew, like software programming, arts and crafts, and digital illustration. It felt like a revolution, opening up the possibility that independent teaching could be a viable profession.

But once again, problems with the marketplace model came to the surface within just a few years. The companies that owned these platforms began to use their control to their advantage, offering deep discounts (sometimes 90% or more) to improve their growth and revenue numbers. Instructors had no control over their own pricing, and could only watch as each new discount brought in less and less committed students for a fraction of the usual price.

The breakout stars of this second wave began to realize that they were giving up far too much: a sizable percentage of their earnings, control over pricing and the student experience, and most importantly of all, the direct relationship with their students. Without the email addresses and payment details of their customers, they were always at the mercy of whatever the marketplaces decided.

The top instructors began leaving the marketplaces, taking their rapidly growing audiences with them. This exodus sparked the third wave: the Toolkits.

Third Wave: The Toolkits

The top instructors from the previous wave had started to make significant amounts of money teaching online. They wanted to build real businesses on their own terms, not on platforms where they had no say. This required them to control their distribution, pricing, and customer relationships.

The Toolkits – led by companies like Thinkific, Kajabi, and Teachable – started to take the lead around 2014 to allow instructors to do just that. These new platforms recognized that the power had shifted to the instructors, who had the original content, the passion for teaching it, and the loyal followers who wanted it. This led them to adopt an “instructor-friendly” approach, treating the course creators as their most important customers, in sharp contrast with the marketplaces, who treated them as mere suppliers.

Instead of standing between instructors and their students, the toolkits shared all email addresses and payment details. Instead of inundating customers with endless cross-promotions, they left the marketing up to each individual instructor. Instead of imposing their own payment systems, they allowed multiple payment options, including monthly payment plans and third-party options like PayPal.

The toolkits allowed course creators to “rent the infrastructure” needed to accept payments, manage student enrollments, host videos and other materials, and communicate with students. Instead of having to hack together a makeshift WordPress site and a buggy plugin, customizing the HTML yourself and troubleshooting as you went along, you could be up and running in hours. As the technology for delivering online courses was increasingly commoditized, the toolkits made it possible to build your own “white-labeled” school, including everything you needed to manage the student experience under one roof (and it was a roof that was completely under the instructor’s control).

This created demand for a new class of user-friendly marketing tools like Leadpages and ConvertKit (affiliate link) to enable these small businesses to capture leads and build their email list. Along with the continued explosion of social media, instructors finally had the tools to directly communicate and sell to their audiences without permission from a gatekeeper.

Some of the biggest names in the emerging movement of “online creators” moved their offerings to their own white-labeled virtual schools. People like Pat Flynn and Amy Porterfield pioneered the path of making a living by building virtual products (such as courses, ebooks, podcasts, subscriptions, events, and content) and selling them directly to their own audience. Teaching online courses became not just a narrow career track, but part of a whole portfolio of digital products and services that an online personality might offer their audience.

I joined Teachable in 2015, moving my previous courses to my own school. There were so many new skills to learn and tools to master – sales copywriting, basic webpage design, how to use email marketing software, among many others. But having access to user-friendly, off-the-shelf tools had finally made it possible for me to control my professional destiny.

The limitations of the toolkit model eventually started to reveal themselves around 2017. As empowering as this third wave was, it demanded too much of instructors. Not just familiarity with multiple kinds of technology, but the marketing skills to attract a continuous stream of customers. Burdened by so many responsibilities, instructors had barely any attention left over for the basic quality of the student experience. The completion rates of these “self-paced courses” weren’t much better than the MOOCs that preceded them.

Primed by hype-driven marketing promising exaggerated results, customers enthusiastically bought tons of courses, only to get busy and watch them collect digital dust. It became clear that self-paced courses demanded too much of the learner: too much time, too much energy, and too much dedication. Relatively few people could muster the self-discipline to make their way through numerous modules of videos, reading, exercises, and quizzes all by themselves.

The failed promises of self-paced courses soured people to the whole idea and gave the industry a scammy reputation.

In response to this, online learning evolved once again. The first three waves had solved the instructors’ problems: how to get content online, how to make money, and how to own an audience. Now the pendulum finally shifted to the students’ problem: how to reliably achieve the results they were promised.

Fourth Wave: The Cohorts

The fourth wave has taken on the name “Cohort-Based Courses,” referring to a group of learners who join an online course together and then move through it at the same pace. The instructor provides structure and guidance, but much of the learning happens peer-to-peer, as students share what they’re discovering in real time and encourage each other to keep going.

Some cohort-based programs (such as Marie Forleo’s B School) embraced the “flipped classroom” model, where pre-recorded content is consumed on students’ own time, and the live classroom is reserved for things that can only happen in real time, like coaching, interacting, asking questions, and sharing breakthroughs. Others (like Seth Godin’s AltMBA) did away with pre-recorded content altogether, opting to focus completely on project-based work executed over a series of short sprints.

I created my own CBC in late 2016, though I wouldn’t have known to call it that until much later. It was called Building a Second Brain (BASB), and taught people how to capitalize on the full potential of their knowledge and expertise, through the practical medium of notetaking.

I designed my course from the bottom up to solve each of the challenges I’d seen students encounter in earlier waves of online learning. I wanted to be able to interact with my students as a coach and a mentor and hold them accountable to the highest version of themselves, so I delivered it live via the emerging Zoom platform. I wanted to work with smart, ambitious professionals doing important work in the world, so I charged a premium price that demanded real commitment. And I wanted a lot of the value of the program to arise bottom-up, out of interactions between students, so I used breakout rooms and a discussion forum for all classwork and exercises.

It’s now been 4 years since that first tiny cohort of 30 people, and over 3,000 people from around the world have completed my course. The outcomes and results they’ve produced have far surpassed anything I ever expected or hoped from an online program. 

In some ways, cohorts aren’t new at all. This is how we learned from grade school to grad school – alongside our peers, with real-time interaction, under the guidance of a teacher. We learned in cohorts because everyone happened to be in the same room at the same time anyway. But this educational format wasn’t easy to deliver online until recently. The popularization of Zoom, riding on the back of ever-expanding high-speed Internet access, made large group video-conferencing frictionless and reliable for the first time.

Cohorts can now come together from dozens of countries, meet any time of the day or night, focus on niche topics that relatively few people are interested in, and adapt the curriculum on the fly. Everything is virtual and digital, which means it is malleable. Since it all has to be recreated anyway, you might as well make changes while you’re at it. This results in a rate of improvement for CBCs that looks more like updates to a software program than a university class.

Instead of teaching the same tired curriculum for decades, a CBC can turn on a dime and incorporate the very latest advancements in the field it is teaching. Instead of paying $100,000 for a degree that doesn’t even qualify you for an entry-level job, you can pay $1,000 for training that was updated yesterday. As more and more industries are rocked by advancing technology, the adaptability of education is becoming ever more important.

What sets cohort-based courses apart

There are 4 elements that distinguish cohort-based online courses from earlier waves:

  • Community
  • Accountability
  • Interaction
  • Impact

Let’s examine each of them.


If you look at how human beings learn, it almost always happens in community. An apprentice watches the master demonstrate the subtlety of their craft. A group discussion explores a question from many different perspectives. The players on a basketball team push each others’ limits to new levels of performance. Even with solitary skills like writing, coming together in writing groups to give each other feedback is a critical part of improvement.

Online forums have been a part of courses since the very first MOOCs, but it would be a stretch to call most of them “communities.” The forum was often just a customer support channel or a list of resources, and many of them were noted for being ghost towns where almost no one participated. Without being able to see each other, hear each other, and share the same experience, fellow students weren’t much more than anonymous icons on a website.

The intensive environment of a cohort is like a pressure cooker for friendships – they can happen in a fraction of the usual time. And not just friendships, but all kinds of relationships: students find mentors, collaborators, thought partners, coaches, advisors, and even clients, employers, or romantic partners. With people showing up live on video under their real names, these relationships can transcend the boundaries of the course and extend out into the “real” world.

Community is an amorphous thing. It can’t be fully planned or predicted. It often takes the form of inside jokes, nicknames, origin stories, and unspoken values. But we can intentionally create the conditions for community to emerge. We can appreciate and elevate those moments and eventually, a true community will emerge.


Cohort-based learning reinvents in a virtual environment the many layers of social accountability and support found in traditional schools: guidance counselors, study groups, teaching assistants, face-to-face class meetings, student portfolios, and final projects.

These forms of accountability support students through the hardest parts of learning, and simultaneously create a culture of high expectations for everyone involved. They are crucial in helping students from a wide variety of backgrounds to successfully complete the program they signed up for. This balance of encouragement and challenge leads to dramatically higher completion rates than we’ve come to expect in online education. Industry-wide numbers are hard to come by, but anecdotally it’s not unusual for the top CBCs to have completion rates of 70-90%, and our most recent cohort had a Net Promoter Score that rivaled the most popular brands in the world.

True accountability comes from being in relationship. It is the relationships we value which prompt us to show up for our soccer team, come prepared to the meeting, or make it to our friend’s birthday party after work. Those relationships can only be formed through direct, meaningful interaction with people we respect. And they tend to happen most naturally under challenging circumstances, with everyone rallying behind a shared goal.

Cohorts naturally provide a strong form of accountability by virtue of being ephemeral. The video calls may be recorded, but they don’t capture the essence of the live experience. This creates a kind of helpful scarcity, where students have to show up while it’s happening or else it’s gone. This also happens to make CBCs strongly resistant to online piracy. Someone can upload your course materials to a torrent site, but the magic of the experience isn’t contained in them. And it very quickly goes out of date anyway.


The live interaction that is only possible via video calls brings many more aspects of our humanity into the learning experience: vulnerable sharing, amusement and surprise, irreverence and wit, laughing and crying, victory and disappointment. These things cannot be conveyed through pre-produced content or a chat-based forum. They emerge spontaneously in an environment where we feel the safety necessary to look into our soul, admit hard truths to ourselves, and step out of our comfort zone.

Live group video creates an environment where many different kinds of interaction can overlap and intersect. Instructors can broadcast one-to-many lectures to present key concepts. Breakout rooms allow students to split off and focus on particular problems or subtopics. Individual students can be brought “on stage” to receive feedback and coaching from the instructors or teaching assistants. Special guests that would never be able to show up in person can call in and share their expertise. And the chat is a lively backchannel full of interesting links, recommended resources, follow-up questions, and affirmation. 

The learning experience that is emerging resembles a video game or a virtual world as much as it does a university classroom. Polls, interactive whiteboards, and emoji reactions enable many-to-many communication that can keep hundreds (or even thousands) of people engaged at once. Students find each other on Twitter, Clubhouse, Slack, and Discord, forming a network that transcends any particular platform. The technology that has for so long been front and center in the delivery of online courses is finally starting to fade into the background. Which is allowing the excitement, the joy, and the fun of learning to shine through more strongly than ever.


There are certain kinds of content that are more easily consumed on our own, such as background reading and how-to instructions. But that content isn’t where the greatest value of education lies. You can always look it up on demand with a Google search.

The true value of education lies in its ability to transform people. It is transformational learning that cohort-based courses are ideally suited for. Learning that shifts people’s identities so much in such a short period of time that they barely recognize themselves on the other side of it.

This level of transformation only happens deep inside communities of practice, where we can feel the safety (and also the sting) of personal accountability. We need the visceral experience of pushing and striving against all odds to overcome a difficult challenge together.

Whether they know it or not, online learners are looking for a rite of passage. This is the opposite of the frictionless convenience we’ve come to expect online. As we all spend ever more of our time on the Internet, there is a tremendous hunger for deeper, more meaningful experiences that stay with us far longer than the latest Instagram story.

The business of education

The structure and accountability of cohort-based courses allows them to do something that was never possible before: demonstrate consistently strong student outcomes. This opens up a world of possibilities: from offering skills that can be used to land well-paying jobs (like coding bootcamps), to offering ISAs (Income Share Agreements) that allow students to pay for the course only after they find paid work (a model popularized by Lambda School).

As quality standards shoot up, the ceiling of how much online educators can charge is also rising. This in turn gives them the resources to invest in the experience: to hire designers to create recognizable brands, train coaches to give targeted feedback, work with technical experts to customize the web interface, and incentivize marketers to reach new audiences.

Course creators can now afford to organize virtual or even in-person events, such as regional chapters for students to get to know each other in person. They can hire a teaching staff, so that the course goes beyond their personal brand and idiosyncrasies. This virtuous cycle of investment is transforming online courses from casual hobbies into real businesses that can promise and deliver on a tangible outcome again and again.

It’s important to realize that each new wave in the history of online education doesn’t extinguish the previous one. It builds on it. EdX (in the first wave) now counts 33 million students taking more than 3,000 courses. Udemy (second wave) generates hundreds of millions of dollars in revenue every year. Teachable (third wave) was just acquired by Hotmart for a rumored quarter billion dollars. In some cases, courses created in earlier waves have reinvented themselves and become part of later waves. For example, Professor David Malan’s computer science course at Harvard, CS50, which has taken on many aspects of live classes delivered via Zoom.

Each new wave adds a new layer of possibility and value to the previous ones. In the same way that the Web is built on layers of hardware, firmware, software, and websites, each wave of online education uses the capabilities developed in previous eras and bundles them into a new experience. Each additional layer expands the scope of things we can do, the people we can reach, and the outcomes we can deliver.

But it is very clear that the frontier of innovation has moved, and the model of sitting in front of a computer watching videos by yourself is no longer the best we can do. Pre-recorded, self-paced content will always have a role to play, but for the transformational education that people are seeking to cope with a quickly changing world, cohort-based courses will be essential.

A new era of democratized learning

The earliest MOOCs promised to make a world-class education available to anyone who wanted it, in any corner of the world.

It’s taken longer than expected, but I believe we are finally on the cusp of being able to deliver on that promise. Some have criticized the expense and exclusivity of cohort-based courses. They’ve been called elitist and overpriced. But I think this new kind of education will make online learning far more open, accessible, and democratic than ever before.

How is that?

First, because it costs money to teach, and it is only when teachers can make a decent living that we will attract the best ones for the long term. When teachers have financial security, they can offer discounts and scholarships to the most deserving students. Without a physical classroom, no one has to spend any money on travel, lodging, or facilities.

Second, because CBCs are unbundling the best parts of the university experience while maintaining (or even improving) their quality. You no longer need a PhD to teach, nor high test scores to gain admission as a student. Instead of expanding traditional universities, with all the bureaucracy, formality, and overhead costs that weigh them down, we can recreate the magic of education in a virtual environment where everyone can pick and choose the parts they’re most interested in.

But most of all, cohort-based courses will democratize online education because they provide the structure and accountability that people need to succeed in their learning. The most underprivileged students are also the ones most in need of that support, and the live interaction that cohorts offer is a far more personalized, responsive, and humane way of providing it.

We’ve spent over two decades figuring out the logistics of how to reliably deliver online courses that change people’s lives. We finally have a business model that is profitable and sustainable, and an audience that is hungry for transformational education.

Now it’s time to bring together everything we’ve learned and all the tools we’ve created to focus all our attention on one question: How do we reliably produce a transformational positive impact on our students?

Thank you to Billy Broas, Dr. Monica Rysavy, Will Mannon, Nasos Papadopoulos, Aditi Parekh, Armchair Traveller, Roshan Mishra, Bhavani Ravi, Chance McAllister, Parth Goyanka, Spencer Kier, Adia Sowho, and Todd Beane for their feedback and suggestions on this piece.

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