manipulating pixels of images and samples of sounds in many of these languages, but my experience suggests that they’re not obvious, not easy to find. Why not? Don’t we think that Donald Knuth is right, and it really is important for CS students to be able to get all the way down easily and obviously to understand how to build it all back up?

There is an argument that real application developers don’t typically work at that level. Video game programmers leave the pixel and sample manipulations to the gaming engine. Most application developers just want to show pictures and play sounds and videos. But that doesn’t excuse not providing access for students. Learning is a conscious process. It’s so much easier to be conscious about things we can see. How do you study something that you can’t see, that you can’t manipulate? How do you learn samples and pixels if they’re always hidden inside some library or engine? Sure, it’s possible to learn things that are invisible, but it works much better if they are visible, accessible, and malleable.

Media is something that I care about, but I wonder if it’s an instance of a larger problem. It’s important for students to shift levels of abstraction. How well do our languages for students support shifting levels of abstraction; that is, being able to see everything from the application level down to the bytes? And if they don’t, we should be asking, “Why not?”

 

Judy Robertson “foggy futures: the confused computing career aspirations of 12-Year-olds” http://cacm.acm.org/ blogs/blog-cacm/115085 July 25, 2011

Can you remember what it was like to be 12 years old and have an infinity of possible careers in front of you? What made you choose computing? Was it a positive choice, or did you drift into it? I have been thinking about this today because I have been listening to recordings of interviews with 12-year-old boys and girls about their attitudes to computing, and their future career choices.

I chose computing because it was difficult. I wanted the challenge. I distinctly remember trying to work out

JuDY RobeRtson
“i chose computing
because it
was difficult.”

how to write a sorting algorithm as I trudged along my morning newspaper delivery route. Naturally because it was so hard it seemed the obvious thing to want to do with my life. (Go figure!) Back in those days, computers weren’t part of everyday life. My exposure to computing was from learning to program at school, and from watching my dad type expert systems code from the back of a book into an Amstrad word processor.

But now, children’s exposure to
computing is ubiquitous and centered
around the use of computers rather
than more fundamental computer
science concepts. In our recent inter-
views with 12-year-olds who had just
completed a game-making project, we
asked them about what they under-
stood by the term “computing.” It be-
came clear that their understandings
were partly related to the label for the
subject on the timetable, such as “IC T,”
“Information Technology,” or “Com-
puting Studies.” None of the classes
were labeled “Computer Science.”
When asked what they might ex-
pect to do in a computing class, the
children typically told us about using
applications: spreadsheets, databases,
PowerPoint, Word, and sound record-
ing packages. The “Internet” was often
featured, in the sense of learning to use
Internet-based applications safely and
effectively. They thought that in a com-
puting class they might learn how to
use computers in general, and learn to
use programs they had not come across
before. A couple of students mentioned
learning about what computers can do,
and what parts are inside them. Oddly,
no one mentioned that they would ex-
pect to study the fundamental proper-
ties of computation, or the patterns for
effective software design.

In terms of future careers, the stu-
dents often explained that while they
thought computing was an important
aspect of many lines of work, it was not
something they wished to focus on. A
boy who wanted to be a pilot mentioned
that “there are a lot of computers in
that. You have to login when you’re go-
ing out and log out and your computer’s
inside the plane.” A girl who wanted to
be a doctor conceded that she would
learn computing if it were necessary to
do the job. Worryingly, a couple of the
girls had misconceptions about how
programming might fit into careers:
Girl A: “To be an optician or a vet,
you have to use the computer quite a
lot for that.”
Girl B: “Programming and stuff.”
Girl A: “To be an optician you have
to program what it is, know what it is,
certain parts. Like what’s wrong, how
they can help and stuff.”
Interviewer: “Have you done any
programming yet in school?”
Girl A: “I don’t know.”
Girl B: “We did. We did our own pro-
gram. ‘My computer of the future,’ that
was a programming project.”
Girl A: “We know that programming
is like typing and stuff.”
Girl B: “Is it?”
Girl A: “So I believe....”
Typing? Opticians? This calls into
question an attitude questionnaire I
recently used that included a perfectly
reasonable-seeming question about
how much the respondent enjoyed pro-
gramming. The results may not be very
reliable if some of the kids think pro-
gramming is merely typing.

Mark Guzdial is a professor at the georgia Institute of Technology. Judy Robertson is a lecturer at Heriot-Watt University.