[OLPC-Philippines] CACM article: Scratch: Programming for All

rayb at apc.edu.ph rayb at apc.edu.ph
Thu Nov 26 21:32:35 EST 2009


Hi Cherry,

Thanks for the comparison, it's a big help.
----- Cherry Withers <cwithers at ekindling.org> wrote:
> Hi Ray and all,
> 
> Here are some things that I found on Squeakland regarding Scratch and Etoys
> comparison. There are pros and cons to both:
> 
> What is special about Etoys? Put your ideas here or send an email to
> squeakland at squeakland.org.
> 
>    - The integration of "etoyish apps"
>       - Graphs: With Ned Konz' "NetMorphs" you could produce things like
>       petrinets <http://scg.unibe.ch/download/petitpetri/>
>       - Kedama
>       - Dr. Geo (to be coming)
>    - Real subroutines (as opposed to Scratch)
>    - Unframed interactive environment for wider and deeper experience. Well,
>    one may say it is a disadvantage because of the white page syndrome it
>    induces...
Yes, the Scratch creators did say they wanted a lower floor.

> 
> 
>    - Clean open source license now (opposed to the source restrictions in
>    scratch)
I just reviewed the Scratch license and it's open enough for me 8^) and I don't think schoolkids or teachers would be concerned about the license either.

> 
> from Bert Fruedenberg's mail (answer to Bill Kerr)
> 
> The power of Scratch lies in its limited scope - several years of
> development and refinement went into it to find the smallest set of features
> that make it easily teachable while still broadly applicable.
Yes, I can see how kids could easily get started on Scratch.  Though I tried it on my son when I first heard of it, and he didn't take to it--maybe he was too young then.  time to try again!

> 
> There are others who could describe the Squeak/Etoys philosophy better than
> me, but one of its core ideas is "no limits".
> 
> Where Scratch is a closed environment, Etoys provides just a thin layer of
> visual scripting on top of a much larger system. There are literally
> hundreds of objects that can be used as building blocks, from basic ones
> like rectangles, ellipses, polygons, or text, to complex ones like a book or
> a MIDI sequencer or video player or a working chess game (in Scratch there
> are only bitmap-sprites). In Etoys you can change coordinate systems, or
> embed objects into each other creating hierarchical animations, or connect
> objects with arrows to create diagrams that are fully scriptable, etc. In
> Scratch, every Sprite is separate, and they can communicate with others only
> by broadcasting - this is more limited but much easier to learn, and less
> prone to errors.
> 
> And if all that is not enough (there are always things the designers can't
> anticipate) Etoys lets you escape to the full Squeak environment. While
> Scratch is implemented in Squeak too, you cannot access it. Again that
> limitation was a conscious trade-off (for example it enables "players" for
> Scratch projects to be implemented in other languages).
This suggest to me that Etoys/Squeak can be the follow-on language for Scratch.  In the CACM article the authors say that Scratchers who "hit the ceiling" should move on to other languages.
 
> 
> Here are a few examples of my own projects in the Squeak showcase that I
> think would be hard to recreate in Scratch.
> 
> Collision Physics
> http://squeakland.org/showcase/project.jsp?id=7052
> (objects with collision sensors adding their forces to influence motion,
> this one is pure Etoys)
> 
> OLPC-XO-Display
> http://squeakland.org/showcase/project.jsp?id=7050
> (adds a new Squeak class to simulate the pixel pattern of the XO's display)
> 
> Euros
> http://squeakland.org/showcase/project.jsp?id=7055
> (connects to a web service to get currency conversion rate using a few lines
> of Squeak scripting)
I'll check this out later.

> 
> One of the fundamental Etoys ideas is that "authoring is always on", hence
> there are no designated screen areas reserved for authoring tools. In fact,
> the tools cannot be used just on the user-created content, but on the tools
> themselves. This is a powerful idea in our opinion, it helps in demystifying
> the tools.
> 
> You can have both tile scripts and textual scripts in Etoys, too. The
> difference is that there is no real need to use the textual scripting for
> the same stuff you can do with tiles. It's to access the advanced features,
> but you will have to know Squeak first to even know what to look for.
> 
> ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
> 
> Cheers,
> 
> Cherry

Thanks again,

Ray
> 
> 
> On Wed, Nov 25, 2009 at 10:59 PM, <rayb at apc.edu.ph> wrote:
> 
> > Hi, all,
> >
> > The cover story of the November issue of Communications of the ACM is about
> > the Scratch visual programming environment:
> > http://cacm.acm.org/magazines/2009/11/48421-scratch-programming-for-all/fulltext
> >
> > Scratch is one of the activities installed on the XO.  A related package is
> > Etoys --mentioned in the article but not discussed further.  About all I
> > know of these packages is that both are implemented in Squeak Smalltalk and
> > both enable multimedia authoring.  So I ask those in the know: which would
> > be better for introducing programming to middle school or high school kids?
> >
> > Best,
> >
> > Ray
> > _______________________________________________
> > OLPC-Philippines mailing list
> > OLPC-Philippines at lists.laptop.org
> > http://lists.laptop.org/listinfo/olpc-philippines
> >



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