[plt-scheme] 2htdp/image questions

On Fri, Apr 23, 2010 at 5:38 AM,  <hendrik at topoi.pooq.com> wrote:
>> Actually, none of it got through clearly. :-( I can only surmise that
>> you would only use cache-image for students not in a beginning course
>> or you would use it in courses for advanced students. The question
>> then is, how many semesters should we expect to keep students using
>> universe? If only "advanced" students are to use cache-image, should
>> these students not be moved on to a different "more advanced"
>> platform?
>
> The *last* thing I'd want to teach them is that functinoal programming
> a la Scheme is inherently inefficient and useless for anything but
> toy programs.

Yes, of course, that is true. However, HtDP is *not* about teaching
Scheme *nor* is it about teaching functional programming. In fact,
HtDP/universe does *not* use Scheme. Granted, it uses a set of small
languages that look a lot like Scheme, but it is important to
communicate to the students that it is *not* Scheme. These small
languages are inefficient in many ways and lack *lots* of features
that Scheme has by default. I can't think of a better way to motivate
students to proceed forward than by encouraging them to learn about
richer languages like Scheme. :-)

In short, we can not say Scheme is inefficient and useless based on
the teaching languages in HtDP nor should we let such a conclusion by
our students go unchallenged. This reminds me of the grade school
problem of adding/comparing apples with apples and oranges with
oranges. My students seem to understand that at varying degrees.

-- 

Cheers,

Marco