[Linux-aus] Re: High school computing texts

[Tim Ansell]

<snip>

> This actually is not about "binary".  It is about "number systems" and
> is part of the fundamental theory and practicality of math.  It does
> not
> make any difference whether it is the decimal, octal, hexadecimal or
> binary base.
> 
> When I taught at the college level many years ago I found a whole
> class
> of students that really did not know what "adding" really did.  They
> had
> learned to "add" through a practice known as "Chisembop" (which I
> wrote
> extensively about in 2005 for LPI):
> 
> http://list.lpi.org/pipermail/lpi-discuss/2005-September/009725.html
> 
> Today I am finding students who "use calculators" and have no idea if
> the answer of "2+2" is "4" or if it is 4,567,237 (because they hit a
> memory register key by accident), and store clerks who look at me like I
> am crazy when I give them a twenty dollar bill and 43 cents in change
> when I have a charge of $10.43 (obviously wanting a ten dollar bill back
> in change).
> 
> Maybe an English student can learn about number systems one time, then
> "relax" a little as they go though life, but a CS student can not.
> 
> And while we are at it, lets talk about really *understanding* what
> "precision" means in floating-point and scientific calculations.
> 
> Sorry, this should be taught at elementary school level.  High school is
> too late.
> 
> Regards,
> 
> maddog

When I was in school, not that long ago (I'm only 23), we use to use
these little cubes (or match sticks). When we got ten little cubes it
got replaced with a large block.

You could use this to count in any base, our teacher even showed us how
to count in base 20 (or other bases with no real practical value) with
this. (IE I have 6 of the little cubes and 9 of the big ones is 69 in
base 20 and 20*6+9=129 in our decimal system.)

Has it really change that much in the 13 years I've no longer been in a
school?

Or does this still create the same problem?

Tim Ansell