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DOI: 10.1145/2380656.2380660
http://cacm.acm.org/blogs/blog-cacm
Levels of abstraction;
Pre-teens and
career choices
Mark Guzdial writes about the need for programming
languages to support multimedia at all levels.
Judy Robertson shares insights about 12-year-old students’
lack of understanding about computer science.
mark Guzdial “Why Don’t Languages upport multimedia ll the Way Down?” http://cacm.acm.org/ blogs/blog-cacm/109917
June 22, 2011
Donald Knuth gave the keynote talk
at ITICSE 2003 on “Bottom-Up Education.” He argued that the hallmark of
thinking like a computer scientist was
being able to shift levels of abstraction, from the highest levels of application, all the way down to the bits,
if necessary. He was arguing for his
MMIX processor, but the same argument can be made in lots of different
pedagogical contexts.
That’s really what Barbara Ericson
and I are doing in our Media Computa-
tion approach to introductory comput-
ing. Students today use digital media
every day. They recognize the manipu-
lation of media as a relevant and useful
activity. In our approach, we teach stu-
dents to manipulate digital sounds at
the sample level and digital pictures at
the pixel level. They can then write sim-
ple loops to create Photoshop-like ef-
fects, like flipping an image or remov-
ing red eye, or to create digital sound
effects, like creating an echo, splicing,
or reversing sounds. Manipulating pix-
els and samples is fun and easy— we’ve
shown that it’s a CS1-level activity. It’s
another case of manipulating the low-
est-levels of abstraction to create an ef-
fect at the application level.
