Dear GA,

You are my last hope.  Having grown up around, beside--and
occasionally inside--televisions, I've seen my share of movies and
commercials, many of which happen to deal with math!  Whenever I catch
the season's hottest differentiating flick ("difs"), however, I have
invariably found the following scenario played out:  a slightly
eccentric professor is standing in front of the class scrawling miles
of equations... ON A CLEAR BOARD.  A CLEAR BOARD!  A CLEAR....ahhh,
you get it.  This is driving me crazy.  No one has been able to
provide a satisfactory response to the following questions:

- What is this clear material?
- What does one use to write on it? (e.g. dry-erase markers, grease
pencil, mascara...)
- Why does it have to be clear?  Are there any distinct advantages a
transparent board has over a white board or the classic chalkboard?
- Is this board actually used outside of Hollywood? If so, why is it
exclusive to science and mathematics instructors?
- ...and... uh... what is the cost of this material, say, per sq.
foot?  Or panel.  Whatever they sell these things by... (cubits?)

I'm losing weight.  I can't sleep at night.  My friends and family say
I'm starting to withdraw.

Please advise.

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Request for Question Clarification by pinkfreud-ga on 23 Feb 2006 17:09 PST

Howdy, sdleex.

I suspect that the transparent messageboards that are often seen in
movies and TV shows are mostly there for looks and dramatic effect.
Only once have I come across one of these in a real-life academic
setting. The board was in an engineering classroom, and I suspect that
maybe it was there just because engineers love cool high-tech gizmos.

Would one of these boards meet your needs?

http://www.magnatag.com/page/KLE/boardb.asp

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Clarification of Question by sdleex-ga on 23 Feb 2006 19:09 PST

Dear pinkfreud,

Thank you for your timely and insightful response!

Call me stubborn, but I can't (...don't want?) to believe clear boards
are strictly for Tinseltown; the fact that you've seen one out in the
wild suggests that they're viable messageboards.  Despite engineers'
love of bling, is there some practical reason to having transparent
boards?  For example, a friend suggested that charts and graphs could
be hung behind the board for easy marking-up.

The link that you thoughtfully provided leads to an acrylic glass
board manufacturer.  Do you know if this is the standard material? 
What other materials are commonly used?

Finally, can you provide some insight/completely make up a reason to
humor me as to why clear boards are a novelty reserved for science-y
types?  I've always thought Hamlet could use some spicing up; maybe
some flair à la "A Beautiful Mind" is just what our favorite prince
needs...?

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Request for Question Clarification by pinkfreud-ga on 23 Feb 2006 19:34 PST

Sorry, but I'm afraid I know very little about transparent boards.
I've only seen one of them up close, in an engineering classroom that
I visited at the University of Tulsa in the early 1990s. I hope
another Researcher will be able to answer your questions about the
materials from which these boards are made and the uses of such
boards. I wasn't able to locate any material other than the link I
posted above.

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Clarification of Question by sdleex-ga on 23 Feb 2006 21:54 PST

Thanks very much, pinkfreud.  I appreciate the link and the anecdote.

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Clarification of Question by sdleex-ga on 23 Feb 2006 22:05 PST

...The entire math faculty at my college has apparently refused to
answer this question.

One way that a transparent board might be superior in a math or
science class would be this: the professor could put the question on
the back of the board, writing it in mirror-reversed fashion so that
it would look right when viewed from the front. Students could then
come to the board, scribble away and erase at will (on the front
side), and the original work would remain untouched. For most schools,
I doubt that this would be important enough to justify the high cost
of the board.

I am sure Pinkfreud can write backwards, probably with her "other"
hand, but I don't see many others being able to do so.

Sdleex,
If you saw these clear boards in films, was it perhaps for the purpose
of allowing the camera to show the professor at the board with the
class room behind him also in the picture?  If so, I expect that the
clear board is only a filming trick to make this possible.  If he
appears to be writing with chalk on the board, obviously it is a
trick, since this would be rather unsuccessful on board with a surface
smooth enough to film through.

Having been in the military I have seen clear boards in use in a lot
of different places, typically in the air control spaces of carriers
and in the Central Control and Damage control. This allows the people
who are listening to the conversations going on to mark the boards
from behind and not obstruct the view of the people who need to
reference the information. They use flourescent grease pencils or dry
erase so that the writing stands out.

Another use that comes to mind is to allow a drawing such as a plant
schematic to be put up and then allow people to mark it up without
destroying the original drawing.

Thank you very much, archamedesii!  I had no idea the military used these gadgets.

If you watch any episode of ER from the past two seasons a clear board
is used all the time displaying patients names and locations.

It seems likely that the material might be plexiglass. I really have
no idea, but it makes sense.