Archive for June 20, 2016

How to choose programming languages for learners: Reviewing JavaScript and Ready

My Blog@CACM post for June is Five Principles for Programming Languages for Learners. The five principles I identify are:

  1. Connect to what learners know
  2. Keep cognitive load low
  3. Be honest
  4. Be generative and productive
  5. Test, don’t trust

I wrote the essay in response to Idit Harel’s influential essay American schools are teaching our kids how to code all wrong. There were many responses to Idit’s essay, on social media and in other blogs. Much of the discussion focused on text programming languages vs. drag-and-drop, blocks-based languages, which I don’t think is the most critical distinction.

In this post, I respond to two of the suggestions that came up in some of these discussions. I use the five principles to review the suggestions in a kind of heuristic evaluation.

JavaScript

If we were going to teach a professional language to students, JavaScript is attractive. It’s free and ubiquitous, available in every Web browser. There are many jobs for JavaScript programmers. Because so much is built on top of it, it’s likely to remain around for many years in a compatible form. I argue in the Blog@CACM post that there are many dimensions to “real” when it comes to programming languages. “Use by professionals” is not the most important one when we talk about learners.

I recommend considering each of these five principles before choosing a programming language like JavaScript for learners.

  1. Connect to what learners know – You could teach JavaScript as a connection to what children already know. The notation of JavaScript doesn’t look like anything that children are likely to have seen before, in contrast to Logo’s emphasis on words and sentences, Squeak eToys’ “Drive the Car,” Boxer’s simple UI boxes (what diSessa calls naive realism), and Racket/Bootstrap’s connections between algebra and S-expressions.  However, JavaScript is the language of the Web today, so one could probably relate the programming activities to Web pages. Most learners are familiar with parts of a Web page, animations in a Web page, and other Web features that JavaScript can control. That might serve as a connection point for children.
  2. Keep cognitive load low – JavaScript has a high cognitive load. I’m a JavaScript learner and am just meeting some of its weirder features. I was shocked when I first read that = is assignment, == is type-insensitive equality, and === is type sensitive equality/equivalence. So, "5"==5 is true, but "5"===5 is false. Counting the number of = and remembering what 1 vs 2 vs. 3 means is an excellent example of extraneous cognitive load. My bet is that JavaScript overwhelms children and is probably inefficient for adult learners. This means that learners are spending so much time making sense of the syntax, it takes them longer and more effort to get to the concepts (and they may lose interest before they get to the good stuff).
  3. Be honest – JavaScript is authentic, it’s real for most senses of the term.
  4. Be generative and productive – I don’t know if JavaScript would be generative and productive for students. I don’t know anyone teaching JavaScript as a way to teach significant ideas in CS or other STEM disciplines. My worry is that the cognitive load would be so overwhelming that you couldn’t get to the interdisciplinary or complex ideas. Students would spend too much effort counting = and fighting for loops.
  5. Test, don’t trustThe only study that I know comparing JavaScript to a blocks-based language had JavaScript losing. JavaScript conditionals and loop structures were far harder for students than the equivalent block-based structures.

We should experiment more with JavaScript, but I suspect that students would do better (struggle less with syntax, learn more, connect to other disciplines more) with a different syntax. If I were trying to get the advantages of JavaScript without the syntax cost, I’d try something like ClojureScript — freely available, as fast as JavaScript, as ubiquitous as JavaScript, used professionally, can be used to control Web pages like JavaScript (so connectable for learners), and with the syntactic similarities to mathematics that Racket enjoys.

Ready

Baker Franke of Code.org is promoting the essay Coding snobs are not helping our children prepare for the future as a response to Idit’s essay. The essay is about the application-building tool, Ready. Media theorist Dough Rushkoff has also been promoting Ready, What happens when anyone can code? We’re about to find out.

I disagree with Rushkoff’s description of Ready, even in the title. As the first essay by David Bennahum (a “Ready Maker and Venture Partner) points out, it’s explicitly not about using a programming language.

Our efforts at Ready, a platform that enables kids to make games, apps, whatever they want, without knowing a computer language, are designed to offer a new approach to broadening access to code literacy.

Bennahum’s essay means to be provocative — and even insulting, especially to all the teachers, developers, and researchers who have been creating successful contextualized computing education:

In this new world, learning coding is about moving away from computer languages, syntax, and academic exercises towards real world connections: game design and building projects that tie into other subjects like science and social studies… This is the inverse of how computer science has been taught, as an impersonal, disconnected, abstracted, mathematical exercise.

I can see how Rushkoff could be confused. These two quotes from the Ready team seem contradictory. It’s not clear how Ready can be both about “learning coding” and “code literacy” while also allowing kids to make “without knowing a computer language.” There is no programming language in Ready.  What is coding then? Is it just making stuff?  I agree with Rushkoff’s concerns about Ready.

True, if people don’t have to code, they may never find out how this stuff really works. They will be limited to the programming possibilities offered by the makers of the platforms, through which they assemble ready-made components into applications and other digital experiences.

Let’s consider Ready against the five principles I propose.

  1. Connect to what learners know – the components of Ready are the icons and sliders and text areas of any app or game. That part is probably recognizable to children.
  2. Keep cognitive load low – Ready is all about dragging and dropping pieces to put them together. My guess is that the cognitive load is low.
  3. Be honest – Ready is not “real” in most sense of authenticity. Yes, students build things that look like apps or games, but that’s not what motivates all students. More of Betsy DiSalvo’s “Glitch” students preferred Python over Alice (see blog post). Alice looked better (which appealed to students interested in media), but students knew that Python was closer to how professional programmers worked. Authenticity in terms of practice matters to students. No professional programmer solely drags and drops components. Programmers use programming languages.
  4. Be generative and productive – Ready completely fails this goal. There is no language, no notation. There is no tool to think with. It’s an app/game builder without any affordances for thinking about mathematics, science, economics, ecology, or any other STEM discipline. There’s a physics engine, but it’s a black box (see Hmelo and Guzdial on black box vs glass box scaffolding) — you can’t see inside it, you can’t learn from it. They build “models” with Ready (see this neurobiology example), but I have a hard time seeing the science and mathematics in what they’re building.
  5. Test, don’t trust – Ready offers us promises and quotes from experts, but no data, no results from use with students.

Ready is likely successful at helping students to make apps and games. It’s likely a bad choice for learners. I don’t see affordances in Ready for computational literacy.

June 20, 2016 at 7:46 am 23 comments


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