Archive for March 2011

How not to Learn from Games

March 28th, 2011 by Paul Horwitz

They’re the in thing, especially for teaching science. Everyone, it seems, is fascinated by the potential of educational games. They’re interactive and “multimedia,” they can adapt to individual students, they promote “authentic learning.” In short, they match the outsize expectations of a digital world. They’re definitely cool, but do they teach, and if so, what do they teach?

Full disclosure: I am an enthusiastic proponent of educational games. I created one called “ThinkerTools” so long ago that it ran on a Commodore 64 computer and had to be programmed in machine language to make it run fast enough. And, yes, I have no doubt that kids learn from such games. But do they learn what we think they’re learning? And how would we know if they were? Is it sufficient that they get better at the game? Surely not, else chess masters would be good at logic, and athletes would be physicists.

It is tempting to imagine that we can design educational games so cleverly that it would be impossible for a student to get good at the game without acquiring a deep understanding of whatever it is the game is trying to teach. Unfortunately, it doesn’t always work that way, as I learned from my experience with another educational game called GenScope.

GenScope was a multi-level genetics game. It linked processes at all different levels, from molecules to ecosystems, and we used it to create a bunch of engaging challenges for students. Our species of choice was dragons. We would show a dragon’s chromosomes, for instance, and ask students to figure out how to change its genes to make the dragon breathe fire. Later on, we would challenge them to breed a strain of blue dragons, or try to find two parent dragons that could only have two-legged offspring (hint: neither parent can have two legs).

We used the GenScope games in several high schools. We compared students who had used the games to others who had learned genetics by conventional means. To do this we designed a clever test that assessed precisely the reasoning skills we were trying to teach—and that we naively assumed were necessary to succeed at the games. Each time we did this, we found that the GenScope classes did no better on the test than the control group. Sometimes they did worse!

In the jargon of the trade the Holy Grail is “transfer,” and we weren’t getting much. Knowledge gained in one context is often difficult for the novice to apply to another one, even though to an expert the two situations appear very much alike.

To us, the researchers, the genetic principles behind the GenScope games were obvious, and their relevance to the questions on the test equally so. Clearly, that was not the case for the students, who became expert GenScope players but failed to apply what they learned to genetics.

There are ways around this impasse, of course, and I will describe a few in a future blog post. For the moment, though, let’s just keep in mind: there are lots of ways of getting good at an educational game. Only one of them involves learning what the game is supposed to teach.

iPad2 HTML5 stats look good

March 14th, 2011 by Chad Dorsey

Sencha has the latest on the new iPad’s HTML5 performance, and the verdict looks quite good:

The iPad 2′s Mobile Safari browser is the best implementation of WebKit on a mobile device. In our testing we tried to throw everything we could at the browser and it had no issues keeping up with the most advanced HTML5 and CSS3 sites. For any developer building for the mobile web, the iPad 2 provides an outstanding platform from which you can use modern browser features.

It will be exciting to see how some of our newest Web-based software performs on this device, especially given these advances.

Reading layers when layers are disturbed

March 4th, 2011 by Sarah Pryputniewicz

Glaciers form when millions of layers of snow compact themselves into ice.  Scientists take samples from glaciers and are able to determine what happened thousands of years ago, just by examining the ice rings.  (See the image of an ice core, below, from Wikimedia Commons.)

19 cm long section of GISP 2 ice core from 1855 m showing annual layer structure illuminated from below by a fiber optic source. Section contains 11 annual layers with summer layers (arrowed) sandwiched between darker winter layers.

Since snow falls on the top, scientists know that the newest layers are on the top, and the oldest layers are on the bottom.  But what happens when the bottom layers aren’t the oldest?

New research in Antartica has shown that new ice was actually being formed at the bottom of the ice sheet as meltwater flowing under the glacier re-froze at the bottom.  This poses a problem for scientists hoping to drill ice cores that go back 1.5 million years.

Still, there’s hope to find that really old ice in Antarctica–it’s just going to take more work to find portions of the Antarctic ice sheet that haven’t melted and re-frozen. Instead of working on the slopes of the mountains of East Antarctica, scientists will have to try drilling at the top of the mountains. At temperatures around -50°F and thin air (equivalent to an elevation of 14,000 feet), that’s no easy feat.

But working in these harsh conditions is the only way that scientists might be able to understand what Earth’s climate was like 1.5 million years ago.