The silver bullet: ZPD!

Spend a few hours in the Ed Psych class I teach, you could easily get the misconception that Vygotsky's Zone of Proximal Development is the correct answer to everything. And you might, I'm afraid, almost be right. "Brush your teeth. Go to church. Zone of Proximal Development."

Today this came up in our discussion of the 2 sigma problem - what makes a difference in a tutoring environment? Maybe it's as basic as the inability for the teacher to simultaneously correctly ascertain the proper zone of proximal development for 30 students. Maybe a tutor, even a peer tutor, is effective because it's an adaptive, responsive human with the feedforward-feedback adaptive abilities to both evaluate your current level and present information at the level slightly above. Maybe a robot teacher (computer program) is ineffective because there's no way we can program in enough variables (constantly changing variables at that) to provide the necessary context for intelligent decisions that enable scaffolding.

But what about the web? Jared asks. Does the web enable us to scaffold ourselves?

For motivated students, yes, Jon says.

But I argue that the web is not an entity, not a robot teacher - the web is just a really easy way to get to other human beings. The web is a tool to enable scaffolding... but there has to be a human on the other side somewhere.

So what does this mean for us now? The discussion came back to our good old friend Mastery Learning. Mastery Learning! Which is only really possible when someone knows if you've really learned - if someone alive and responsive can go through those processes with you, they're providing that scaffolding feedback.

So is the ZPD our silver bullet? Is mastery learning our silver bullet? Are ZPD and mastery learning really kind of the same thing? Do I get any extra points for brushing my teeth and going to church? Interesting things to keep in mind...

Robot Teachers

Class notes: where have we gone with this 2 sigma question this semester?

What I want to know is: are computers really the answer? Do we believe that? It seems that's where all the research has gone ever since Bloom's 1984 article - we automatically assumed "Well, that's easy. We'll make robot teachers."

Which means, of course, that the science fiction authors were all right! Right?


Do you like my disturbingly gross over-simplifications? That's actually my only talent here.

Dr. Wiley's first topic - Anderson's work in intelligent tutors. "Reflctions of the Environment in Memory" - Anderson and Schooler - basically, frequency, recency and pattern determine what we keep in our memories and what we throw away. Because this is the way our environment is structured, this is the way our brains have decided to store information. Very interesting.

So what does this have to do with robot teachers is what I want to know. Oh good, he's getting there.

Carnegie Mellon's Open Learning Initiative - uses "mini cognitive tutors." A study shows that students who use these online tutorials in hybrid mode learn faster and better than students in face-to-face classes. My next question, though, is - how do the hybrid students do compared to the online-only students? And this is where I think the sci-fi authors really missed the mark.

What did they think we'd have by the year 2010? Robot teachers, right? Automated teaching machines. Computers that talk to you and ask you questions. Pills that taste like food so you don't have to eat. We don't have any of that, though, do we? We failed! But what do we have? We have Wikipedia. And Omega-3 enriched eggs.

Here's what I say, though - Wikipedia is way cooler than robots. We outdid the sci-fi authors. Why? Because computers are dead and lifeless and can't simulate the human brain. But when you put the human brain - no, 153 million human brains - in computer skins, then they can do cool things. The hybrid is doing things that the machines will never do.

OK, off of the tangent train. Back to class:

The Open High School (Dr. Wiley's specialty) - There are two things a tutor does: 1. information provision (broadcast function), 2. Q/A, diagnostic help, support
#1 is automated - one teacher writes one lecture, makes it available online, rather than giving 6 lectures. #2 is partially automated in terms of data analysis, who's doing what, etc., the actual teacher is doing the 1-on-1 connection

Again - the hybrid human/machine is doing more and doing it better than a human alone or a machine alone can do. This is fun! Class is over though. Remind me to come back to this.

(Get your robot teacher to send me an email or something)

Where should we go from here?

Create a research agenda for creating a tutor-like environment for education. Where should our attention be placed? What tools are emerging that we could use to give people access to something even better than an individual tutor?

I'm still torn on what the main focus is here. It seems like, of the literature we've seen, most has been focused on technological solutions to the 2 Sigma Problem. This is good, but in a lot of the subsequent literature in the 90s we pursued technological replacements for the tutor, which ended up as rather fruitless searches.

What I want to know is: why didn't more research follow the mastery learning thread that Bloom himself started? Mastery learning was far more effective than anything else at approaching the 2 sigma level, but we seem to have given up on that option and instead focused on what we can do to make a computer act like a human being. Why on earth would we abandon the most promising pedagogical approach? Well, I mean apart from the fact that it is totally incompatible with the No Child Left Behind approach to education where we divide up learning into totally inauthentic and arbitrary chunks and proscribe an approach to teaching that is not only frustrating for the teachers but entirely contrary to everything we know as best practice; other than that, of course, why would we do this?

I appreciated the Chi, et al. study that sought to find out what about the tutoring experience made it effective. Its findings suggested that it isn't the tutor's bank of knowledge that makes a difference, (the "suppressed tutoring" was just as effective as "normal" tutoring) but rather the structure; the interactive environment that is making a difference.

So what I want to see us do is to explore the pedagogy of tutoring and find out how to change our classroom structures to better replicate it (or tear down the classrooms altogether). Especially in an age where internet technology allows access to information that a "sage on the stage" didn't need to memorize, we have such a capacity to change the way we teach and learn. Web 2.0 and communicative technologies allow us to extend the reach of the human tutor and the interactive environment. Instead of trying to figure out how to make computers think like humans, let's try to use our computer technology to increase the capacity and number of human tutors.