Education: Head of the Class

Technology hasn’t always been ateacher’s pet –but it could very well end up as our greatest teacher. In this episode, we explore how.
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All a board

Picture an educational setting –a classroom. If you’re in the US, it stands to reason that many of you pictured the same thing: a blackboard on the wall. And it’s remained that way for a century. Ever since children were batched by age and moved through the school systems like assembled products, the chalkboard became the quickest and easiest way to reach a group full of children learning at the same pace.

Learning in a flash

Technology entered the classroom in the post-World War II era, but for many years, educators struggled with exactly how to incorporate it in a way that makes sense or didn’t detract from the established learning model. There were transparencies, teaching machines, television, radio, movies, and magic lanterns and so on. All had their moment in the sun –none were as easy as A-B-C to implement, or seemed to have any real practical application or staying power initially.

Changing models. Changing lives.

As access to computing, and –in particular –the Internet proliferated, classrooms began to better incorporate digital technology into learning. They did so by gradually moving away from the established time-based learning model and into more of a “mastery” model. By augmenting brick-and-mortar education with online, self-directed learning, students were able to learn at a pace that best suited them. How far away are we from taking the blackboard off the wall? Find out in this episode.

“I think teachers are at the final frontier of anything AI will ever do, because teaching is inherently a human endeavor.”


What you’ll hear in this episode

  • The uneasy origins and enduring legend of the blackboard
  • The industrialization of education
  • Things keep changing, but the classroom remains fundamentally the same
  • What’s a “teaching machine?”
  • In-classroom computers were, initially, more of an accent piece
  • The high expectations, and tepid reception of educational technology
  • What technology is really, really good at with respect to learning
  • The “mastery model”
  • Free world class education to anyone, anywhere
  • Augmenting teacher-led instruction with online learning in the classroom
  • “It’s somewhat ironic that you can use technology to humanize a classroom.”
  • We’re mere moments away from AI truly making the grade

Guest List

  • Audrey Watters Is an independent scholar who writes about education technology -- its politics and its pedagogical implications and the author of The Monsters of Education Technology.
  • Michael Horn Is the Principal Consultant at Entangled Solutions and the co-author of the book Disrupting Class: How Disruptive Innovation Will Change the Way the World Learns.
  • Thomas Arnett Is a Senior Research Fellow at the Clayton Christensen Institute and author of Teaching in the Machine Age: How innovation can make bad teachers good and good teachers better.
  • Larry Cuban Is a Professor Emeritus of Education at Stanford University. He teaches courses in the methods of teaching social studies, the history of school reform, curriculum, and instruction, and leadership.
  • Sal Khan Is the founder and CEO of Khan Academy, a nonprofit with the mission to provide a free, world-class education for anyone, anywhere.
  • David Dockterman David Dockterman lectures at Harvard and helped launch the field of education technology surrounding the use of computers in the classroom in interactive and engaging ways for teachers and students.

WALTER ISAACSON: It’s the early 1800s, and we find ourselves in the classroom at the old high school in Edinburgh, Scotland. The school’s headmaster, James Pillans, stands in front of the room. He’s about to change the face of education as we know it through a very simple and completely revolutionary act.

James Pillans had been looking for a new tool to help teach geography to his students. He would explain his revolutionary idea in a book he would write almost a half century later.

WALTER ISAACSON: “I placed before my pupils a large blackboard having an unpolished, non-reflective surface on which was inscribed in old relief a delineation of the country. The delineation was executed with chalks of different colors.”

WALTER ISAACSON: By hanging a bunch of his students’ slate tablets together on the wall, James Pillans had created the first blackboard. It’s one of the oldest but still the most recognizable and useful pieces of classroom technology ever invented.

Walk into any kindergarten to grade 12 classroom today, and chances are it will be there. Dominating the front wall of the room just like it did 50 years ago, 100 years ago, even 200 years ago. Most classrooms offer a learning experience that has largely remained static. But that’s all poised to change as we find ourselves on the verge of what may be the biggest disruption that the classroom has ever seen.

I’m Walter Isaacson, and you’re listening to “Trailblazers,” an original podcast from Dell Technologies.



MAN: It’s only right that every child should have adequate educational opportunity.

Boys and girls who show great intellectual promise.

They study a variety of subjects.

Long division and irregular verbs.

The laws of motion and chemical combinations.

Let’s take a glimpse at today’s meeting of The Breakfast Club.

WALTER ISAACSON: There’s actually an important lesson to be learned from the way the blackboard was rolled out across American schools. You’d be tempted to think that its benefit was so obvious that teachers would embrace it enthusiastically. But that’s not what happened, at least not initially.

David Dockterman is a lecturer on education at the Harvard Graduate School of Education.

DAVID DOCKTERMAN: I started going through the school reports in Massachusetts and Connecticut in the early 1800s and I ran into these observations about teacher’s lack of use of chalkboards. They’d invested heavily in putting blackboards, chalkboards in all these classrooms, and then were lamenting that the kids knew how to use them better than the teachers did.

And I was just flabbergasted because I never pictured the chalkboard as something that was complicated to use. And as I dug deeper, what I found was that the enthusiasm for chalkboards among educational reformers came from watching university professors. And that still was an innovation, seeing a professor up on a stage with this big piece of slate and dynamically illustrating a lecture as he spoke.

WALTER ISAACSON: But there was an important difference between the university classroom and the primary grade classrooms that those reformers failed to take into account. In the university classroom, all the students were learning the same subject at roughly the same level at the same time. But that was not the case in mid 19th century primary schools. It was still the era of the one-room schoolhouse. Students of all ages were learning different things at different levels.

DAVID DOCKTERMAN: Those one-room schoolhouses sometimes got 100, 200 students. And so it got pretty complicated. So when they put a device in for teaching large groups, it didn’t make sense. It wasn’t that it was technically complicated. It didn’t match the pedagogy of the time. Teachers were not teaching to large groups, they were teaching to small groups.

WALTER ISAACSON: David Dockterman Mann believes that what happened to the blackboard was a case of premature disruption. Technology, no matter how useful, can’t be introduced without taking into account what’s actually happening inside the classroom.

DAVID DOCKTERMAN: Pedagogy drives acceptance. For things to work, they have to fit the culture, the pedagogy, the demands of managing a classroom. And it’s not that teachers don’t want to be successful and don’t want to do well for students. But they’re in a culture that is sort of self-sustaining. And so throwing a new piece of technology into that system, to expect it to change the system, we just don’t have any examples in history of that happening.

WALTER ISAACSON: Of course, the blackboard eventually did gain wide acceptance. But it didn’t happen until the American model of education changed dramatically in the latter part of the 19th century. Waves of immigration caused the population of urban centers to swell. There were more children than ever before that needed to be educated, and they certainly weren’t going to fit inside a one-room schoolhouse.

And so Americans looked for a new model for educating millions of students from kindergarten through high school, and they were inspired by a new method of mass production that was then revolutionizing the American economy.

Michael Horn is the Chief Strategy Officer at Entangled Ventures, a San Francisco-based education technology studio.

MICHAEL HORN: When America was industrializing, the pattern of work was based on a factory where we would batch products up on assembly lines, add value to them at different stages, and then ship them out on the other side as finished products.

And when we were trying to move to a mass education system at the turn of the century, we emulated those factories by basically saying we’ll batch students up based on date of manufacture, otherwise known as age, in what we call classrooms. And we’ll add value to them in the same day, same space, same way, and then ship them out on the other end. And some of them will master concepts and be able to move on to higher education, and some of them won’t. And we’ll ship them out into jobs in the industrial economy.

DAVID DOCKTERMAN: And it made sense, in many ways, from an efficiency point of view.

WALTER ISAACSON: David Dockterman.

DAVID DOCKTERMAN: Because theoretically, nine-year-olds are about the same. And then you could train teachers to be experts in teaching nine-year-olds, and other teachers experts in teaching 12-year-olds. And it is a very much kind of factory model where you’re being very efficient, very effective, and you have experts devoted to their job. And now you had a shift.

And the structure of schools changed, groups of common age kids all learning the same thing. And all of a sudden, the chalkboard made sense and it became a standard part of the system, a really cherished piece of technology.

WALTER ISAACSON: By the early years of the 20th century, the American education system had reached its modern form, and for nearly 100 years, it changed remarkably little. Students remained grouped in grades based on age rather than competency, and the blackboard remained the dominant piece of technology.

There were challengers, of course. In many ways, the story of instructional technology in American schools is a story of educators chasing an elusive dream. Each new innovation showed enormous potential for disruption. And while they all made important contributions to learning, none had the transformative impact its proponents envisioned.

The magic lantern was one of the first. It could project images on a glass plate. By the end of World War I, the Chicago Public School system had a collection of 8,000 lantern slides. But by then, interest had already turned to the revolutionary potential of film in the classroom.

In 1910, the city of Rochester, home of the Eastman Kodak Company, became the first city in America to officially adopt film for instructional use in its schools. And Thomas Edison predicted that motion pictures would soon replace books in the classroom.

Meanwhile, radio was starting to make its presence felt. In 1923, Heron High School in New York City became the first public school to use radio in classroom teaching. It all looked very promising. But Edison’s prediction about film in the classroom proved to be widely off the mark, and radio never lived up to its initial promise either.

One of the reasons was that the opinions of the people who knew most about what was needed in the classroom were rarely solicited. Nobody bothered to ask the teacher.

Audrey Watters writes about education technology and is currently the Spencer Education Fellow at the Columbia School of Journalism.

AUDREY WATTERS: I think that part of the problem with the adoption of new technologies, whether it’s film or radio or television or computers, is that often teachers feel that these new technologies pose some sort of existential threats because teachers feel like they’re very much left out of building these new technologies.

WALTER ISAACSON: But lack of teacher input wasn’t the only problem. For David Dockterman, the difficulties that plagued the introduction of instructional film, radio, and later television demonstrate the perils of taking technology primarily developed for mass entertainment and transferring it to the classroom.

David Dockterman.

DAVID DOCKTERMAN: You can look at history with the statement, you know how people love? And you can go back to even magic lanterns. You know how people love going to lantern shows, because that was sort of popular entertainment. You’d see these big pictures on the wall. And it’s like, wow, people love doing that. Let’s bring that into school. You know how people love going to movies. Let’s bring movies into school.

And Thomas Edison wrote about how a big army with swords and guns won’t be able to keep kids out of school because they’ll be rushing in to watch movies. In fact, we probably won’t even need schools. You’ll learn everything you need in movie houses.

You know how kids love doing video games? You know how kids love playing with computers? Well, that’s what we’re going to– we’re going to bring that love of stuff outside of school into school, and somehow magically it’s going to turn into education. And that just hasn’t happened.

WALTER ISAACSON: By the mid 1950s, a new technology emerged that was designed not to entertain students in the classroom, but actually help them to learn.

B.F. SKINNER: These young people are studying in a new way. A class in spelling. it might as well be arithmetic or algebra or grammar, or, in fact, anything involving the use of words or symbols. Each student is using a teaching machine, a device which creates vastly improved conditions for effective study.

WALTER ISAACSON: That was the renowned Harvard psychologist B.F. Skinner, touting his teaching machine in a promotional film released in 1954. Skinner was a pioneer in what was known as programmed learning. The idea, gleaned from his study of animal behavior, was that learning was best accomplished by small, incremental steps with immediate reinforcement for the student.

On Skinner’s teaching machine, students were presented with a question. They wrote their answer on a screen and were immediately informed if they were right or wrong. In his autobiography, Skinner wrote that the idea for the teaching machine came after a visit to his daughter’s fourth grade classroom.

Audrey Watters.

AUDREY WATTERS: He visited his daughter’s fourth grade classroom. He was shocked, he said, to see that the students were required to move through the lesson at the same pace. He thought this was wildly inefficient. And then when students were asked to do worksheets, to do assignments, he was gravely concerned that they wouldn’t get feedback on what they’d done until a day or two later.

And so his idea was to create a machine that would make the classroom more efficient so students could move at their own pace and so that students would get immediate feedback whether they had an answer right or wrong.

WALTER ISAACSON: Despite being revolutionary, Skinner’s teaching machine was never widely adopted in American classrooms. At $6,000 apiece, it was out of the range of most school budgets. And already looming on the horizon was a new machine that could do everything the teaching machine could do, and potentially a whole lot more. It was called the computer.

Computers first started appearing in American classrooms in the early 1980s. But in those pre-internet days, their utility was fairly limited. David Dockterman was teaching high school when the first computers arrived.

DAVID DOCKTERMAN: I resented the technology that was being brought into our school. There was an effort to bring in Radio Shack Model 3 computers. And I remember you know people coming in to do a little in service for us and show us what these machines could do. And the game was something like– it was like a states and capitals game. And so you had a timer, and you have to identify the name of the state or the capital before the timer ran out or New Jersey would blow up.

Now New Jersey blowing up wasn’t so bad. But the game is just– it’s like, wait, you want to invest in that while you’re paying me $9,000 a year? That’s just crazy. Pay me more, give me a little more time, and it’s going to be much better than that. So we’ve often been faced with this push to bring technology in without much evidence that it’s going to make much of a difference.

WALTER ISAACSON: Teachers may have had reservations about what these new machines were doing in the classroom, but by the late 1980s, the frenzy to have computers in the classroom had begun. They were promised to be the ultimate disruptors. But have they been?

The people proclaiming the transformative impact of computers in the classroom were basically making the same mistake as the early proponents of the blackboard. They were imposing a potentially disruptive technology onto an already existing pedagogical model and expecting everything to change.

Larry Cuban began his teaching career in the mid-1950s. He’s now a Professor Emeritus of Education at Stanford. He recalls that expectations were sky high about what computers in the classroom could achieve.

LARRY CUBAN: The intentions were to completely redesign the schools, and particularly redesign classroom teaching by entering these machines and devices into classrooms. That was the intention. But what happened over time is that most teachers found it helpful to a certain degree, but still relied on the blackboard, textbooks, and other kinds of low tech tools that they’d been using for years. And the nature of the school hasn’t changed very much. And the advocates have turned out to be very disappointed in what has materialized in classrooms and schools.

WALTER ISAACSON: A classroom in the late 1980s or early 1990s might have had one or two computers at the back of the room and 30 students hoping to get a chance to use it. And when their 10 minutes finally came along, there was nothing that really connected the students’ limited computer time to what the teacher was doing the rest of the day.

LARRY CUBAN: There are, you know, some bright spots. Access to digital tools has increased exponentially in the last 15 years. The number of students per computer has fallen dramatically. In the early 80s, it was 125 students to one computer. Now it is somewhere between two and three students per computer, and in many places it’s one to one. Every kid has a tablet or a laptop.

WALTER ISAACSON: It turns out that having a computer was one thing. Doing something useful with it was quite another.

LARRY CUBAN: Well, the distinction I make every time I talk to someone– and it becomes nauseating, I assume, to some people– is that access is one thing, use is another. In 2016 I visited 41 teachers who had the reputation of integrating daily digital tools into their lessons. And I was very impressed with them.

But the digital tools were not front and center. They weren’t in the foreground, they were in the background, just like paper and pencil. They help the teacher do what he or she wanted to do to reach the goals of the lesson, but it was not disruptive by any means.

WALTER ISAACSON: And today, 30 years after computers first appeared in the classroom, Michael Horn believes those early lessons have not been learned well enough.

MICHAEL HORN: A lot of times I think the goal, as a district or teachers or community implements technology, is to say we’re implementing iPads because we have digital natives and therefore everyone needs iPads. And it’s a circular argument, right? It’s technology for technology’s sake.

And what we suggest is that instead, you should be thinking deeply about what’s the instructional or educational reason you want to use the technology? Lead with that, and then use the tool in service of that. And technology is amazing at certain things like transmission of knowledge, allowing people to practice problems over and over and over again and get robust feedback about where they’re struggling, advancing in lockstep with students’ abilities, and things of that nature. But you really need to start with that educational goal first and foremost, rather than technology for its own sake and getting excited about it.

WALTER ISAACSON: For education reformers like Michael Horn, the key to unlocking the transformative potential of computers in the classrooms lies not in some shiny new technological bauble, but in fundamentally changing the way students are taught, no matter how difficult that might be.

MICHAEL HORN: Yeah, it is not easy to change the model. There are tons of incentives, practices, entrenched interests that have just accumulated over time, many of which we don’t even think about because we just assume that’s how schooling is done, rather than question them as core assumptions.

And indeed, many times community members, parents, are the obstacle to moving to these systems because that’s not how I learned and I turned out OK, so why are you trying to change the instructional model?

WALTER ISAACSON: The primary stumbling block from Michael Horn and other reformers is the century-old factory model of learning, where students are grouped in grades according to age, and they are all expected to learn at roughly the same pace. As long as that system is in place, they argue, the chalkboard might actually be the most suitable classroom technology. But they’re convinced that there’s a better way.

MICHAEL HORN: Our system is fundamentally a time-based system, which means that time is the constant. You’re going to spend a certain number of days, a certain number of hours, a certain number of minutes learning. And then every student’s learning is highly variable. Some people master material in the amount of time that they have. Some people don’t. And we test at the end of the year and just figure out what percentage of them got enough of it right and what percent of them didn’t.

That’s fundamentally not a model built around learning. It’s built around time. And you can imagine moving into a mastery-based model where students now progress based on mastery of material. So the learning is the constant and the time becomes the variable.

WALTER ISAACSON: A mastery-based model of learning is rooted in the fairly simple idea that not everyone learns in the same way at the same pace. Learning is more personalized, and technology is simply a tool educators use to put the student at the center of learning.

SAL KHAN: You know, the technology is never going to be like a true human personal tutor. But it can help address parts of it, or it can help empower a tutor to better personalize. And what we’re advocating, and we see teachers doing more and more, is these types of tools can be leveraged by a teacher who’s teaching 30 students. But now they can actually reach each student where they need to be.

WALTER ISAACSON: That’s Sal Khan, a man who never set out to be a trailblazer in the world of education. But that is precisely what he’s become. In 2004, he was a year out of business school and working in finance in Boston. Some family members came up to visit from New Orleans.

SAL KHAN: My 12-year-old cousin Nadia was having trouble with math. So I offered to tutor her remotely when she went back to New Orleans. We did that for a couple of weeks. She got caught up with her math class. Then, frankly, she got a little ahead of her math class. She went from being in a remedial math class to an advanced one.

So I was hooked. I started tutoring her younger brothers. And then over the next about year, two years, word gets around the family that free tutoring is going on. And I find myself working with about 10, 15 cousins all over the country. So I started writing a software practice platform for them.

I was showing this off to a friend, and he says, well, this is cool, Sal, but how are you scaling up your lessons? And I told him yes, that’s hard to do with 10 cousins what I was originally doing with one. And he said, hey, why don’t you record some of your lessons as videos and upload them onto YouTube for your family?

And I immediately thought it was a horrible idea. I said, no, YouTube is for cats playing piano, not serious mathematics. But I got over the idea that it wasn’t my idea and gave it a shot.

WALTER ISAACSON: From this humble beginning, Sal Khan created the nonprofit Khan Academy in 2006 with the stated goal of providing a free, world class education to anyone, anywhere.

12 years later, the Khan Academy has produced over 6,500 online instructional videos on every imaginable topic. They have been translated into more than 36 languages and viewed more than a billion times. Millions of students and teachers around the world have been helped by them.

Of course, Sal Khan wasn’t the first person to produce instructional videos. He wasn’t even the first to put them on YouTube. But these videos resonate because they continue to feel like one cousin helping a younger cousin with their homework. They don’t condescend. They don’t make the user feel stupid for not understanding the material.

But what has been truly disruptive about what Sal Khan has done is not the videos themselves, but how they are being used. It was called the flipped classroom. In the traditional model, the teacher used class time to teach a lesson and then sent students off with homework to see if they understood it.

In the flipped classroom, the student would learn the lesson at home from a Khan Academy video, and the teacher would use the class time to enrich and elaborate on it and help students who were struggling.

SAL KHAN: So in the early days of Khan Academy, I got letters from teachers saying hey, you gave a solid explanation of photosynthesis so I don’t have to use my precious class time to re-give that explanation. My students can watch it on their own terms. And then when they get to class, we can do an experiment, we can have a discussion, we can do some problem solving.

And they are the ones that explained to me that they had essentially flipped the model. What used to happen at home, which is the problem solving, now happens in class with support from the teacher and the peers. And what used to happen in class, which is getting your baseline instruction, could now happen at a student’s own time and pace.

Now I think that’s a very, very good thing. And it’s not a new idea. This has been happening in humanities seminars forever. Read the book, and then when you come to class, we’re going to discuss it. The teacher wouldn’t read the book to you. But what’s powerful is that now this could happen in all classes, especially science and mathematics classes where it historically hasn’t.

But what I advocate goes much further than that, because once the classroom is no longer about synchronous information delivery, you don’t have to make everyone do the same thing at the same time.

WALTER ISAACSON: While this blended learning approach represents a sharp break from the old age-based factoring model, it’s not about eliminating the classroom or doing away with teachers. In fact, in 2014, Sal Khan himself opened a bricks and mortar school in California called the Khan Lab School.

SAL KHAN: When I first said I want to start a physical school, a lot of folks looked at me strangely, like, hey, you’re doing this virtual thing, it scales, are you’re reaching millions of people. Why would you want to start a physical bricks and mortar school?

And I said, look, the whole point of Khan Academy is not to somehow– and I don’t like the word disrupt– traditional education. It isn’t Amazon versus Barnes and Noble. It’s all about to liberate the physical classroom. And as now I have three children, the last thing that I would want is my children to be learning purely from a computer all day, that the biggest part of learning are the human connections, the human experiences.

And so we set up Khan Lab School in order to prove that out, to say, OK, if these types of tools exist, what could the whole structure of learning look like? You know, the thing I always talk about is this– it’s somewhat ironic that you can use technology to humanize the classroom.

WALTER ISAACSON: When integrated correctly, technology is used to serve and enhance what the teacher is doing in the classroom. And it gives students ownership of their education. When it’s not done well, the technology is imposed on the teacher without proper training or preparation.

Thomas Arnett is a Senior Researcher at the Clayton Christensen Institute, a nonpartisan think tank that studies how innovation transforms society.

THOMAS ARNETT: In fact, I’ve met and talked to many teachers that will say blended learning or new uses of technology in my classroom are fantastic. But for every teacher that gives that kind of feedback, there’s also a handful of teachers that say this was just way more work. I didn’t see the benefit. It just created more distractions in my classroom. It created more things that I had to manage, made my job harder. And I think that question of how is this helping the teacher is one that the field isn’t asking enough.

WALTER ISAACSON: And with artificial intelligence increasingly making its presence felt inside the classroom, teachers may someday have even more access to tools and data that enrich learning. AI software may someday be able to read and grade a student’s paper and give feedback, perhaps even as useful as most teachers could. And that’s just the beginning.

But Thomas Arnett believes even in an AI world, the teacher’s role in the classroom will be as critical as ever.

THOMAS ARNETT: If the teacher is just sitting on his laurels and letting the software give his students scores, and then just copying those scores into his grade book, I would say that’s a problem. But if the software is giving the student a lot of coaching on things like the style and the structure and the grammar of the student’s essay– so the teacher doesn’t have to worry about those things when he sits down with a student and can just talk about voice and rhetoric and how persuasive they are in their writing and reaching their particular audience– that’s the value. So there always needs to be a human value add from the teacher on top of what the AI is doing. If we just outsource everything to the AI, we end up with pretty crummy education.

WALTER ISAACSON: There’s a joke that educators like to tell about Rip Van Winkle. They say if he woke up today, 100 years after his deep sleep, the only thing he would recognize in the world around him would be the classroom. It’s been the one great constant in American life.

But that’s increasingly no longer the case. The classroom has changed more in the past 10 years than in the previous 150, and the pace of change will continue to accelerate.

Where it all ends remains an open question. There have been so many false starts when it comes to adopting technology in the classroom, so many lessons that were not well-learned. But today, many people who work in education are convinced that we may finally be on the right path. Is it time to take the blackboard off the wall?

I’m Walter Isaacson, and you’ve been listening to “Trailblazers”, an original podcast from Dell Technologies.

Next time on “Trailblazers”, we’ll delve into the game of golf and hear the story of how military radar tracking is threatening to disrupt the whole game. For more information on how technology is changing today’s classroom, you can check out our website at Thanks for listening.