squeakland December 2007

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22 participants
21 discussions

Buck Inst ?
by Randy Heiland 05 Dec '07

05 Dec '07

An open-ended question for the educators (or anyone else) on this list. Has anyone heard of/have experience with the Buck Institute and their Project Based Learning stuff (www.bie.org). I ask simply because our small town here in southern Indiana is supposedly starting a "first-in-the US" New Tech *elementary* school that will be based on this. thanks, Randy

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looking for some advice on teaching Squeak to advanced high school kids
by Oscar Nierstrasz 04 Dec '07

04 Dec '07

Hi Folks, I teach at University level, not high school, and have no previous experience teaching high school kids. At the end of January we will have a day and a half with a bunch of high school kids who are finalists in the Swiss Scientific Olympiads ( http://www.olympiads.ch/ ) and have the opportunity to get them excited about computer science. We will have various sessions to show them different things. (I will not be the only one to offer something. A colleague will be introducing the ones who have no background in programming to Scratch.) I wanted to take the ones who have done some programming (i.e., those who have done the Swiss Olympiad in Informatics - http://www.soi.ch/ ) and introduce them to Squeak. For the Olympiad they have been working with languages like Pascal, C and C++. I would like the session to be mainly hands-on, and get the kids to actually build something in teams of two with help from some monitors. Does anyone have any experience like this? Can you recommend some specific exercises that would be fun and would produce a real result in a few hours? My concrete goal is to show them how different a dynamic language and environment like Squeak can be from the languages they are used to. Any hints would be welcome. - on --- Prof. Dr. O. Nierstrasz -- Oscar.Nierstrasz(a)iam.unibe.ch Software Composition Group -- http://www.iam.unibe.ch/~scg University of Berne -- Tel/Fax +41 31 631.4618/3355 vcard: http://www.iam.unibe.ch/~oscar/oscarNierstrasz.vcf

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OLPC / plugin timeframe?
by Mark Nelson 04 Dec '07

04 Dec '07

Sorry if this has been covered recently, but what's the rough timeframe for a new browser plugin that's compatible with the OLPC version of etoys? I'm planning to develop some new educational simulations, and would like to use the OLPC version, but I'd also like the projects to run in a web browser. (Is there any way to do this using the existing plugin?) I know efforts have been focused on getting code for the XO finalized, but now that mass production is underway, will a compatible browser plugin be appearing soon? --Mark

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Seeking Tutorials on Serial Port I/O in Squeak
by Eric Eisaman 03 Dec '07

03 Dec '07

Hello Squeakers, For some time now I have been building capacity in myself and my students to engage handcrafted peripherals in Squeak programs. Are there any programming tutorials which taper a new learner into this type of venture in maybe EToys with some added Smalltalk code? Eric Eisaman Guam

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The clock face - Panel discussion: Can the American Mind ...
by Tony Forster 03 Dec '07

03 Dec '07

>> My mental model for arithmetic is a clock face, The clock face is an interesting programming challenge for languages like etoys, Scratch and Game Maker which provide good graphics support. It provides a good context for problem solving and exploring trigonometry. See a clock at http://www.schoolgamemaker.rupert.id.au/morethan.htm programmed with Game Maker. It is worth considering what kids would gain from such an exercise and how the features of the various languages would affect the learning. How do the languages compare for depth of learning and ease of use (engagement)? It is only through considering these questions that Squeak can be made as good as it can be. Anybody want to create a clock in etoys or Scratch for comparison? Here is the Game Maker code draw_circle(200,200,130,true) x2=200+100*sin(2*pi*current_second/60) y2=200-100*cos(2*pi*current_second/60) draw_line(200,200,x2,y2) x2=200+100*sin(2*pi*current_minute/60) y2=200-100*cos(2*pi*current_minute/60) draw_line(200,200,x2,y2) x2=200+50*sin(2*pi*(current_hour+current_minute/60)/12) y2=200-50*cos(2*pi*(current_hour+current_minute/60)/12) draw_line(200,200,x2,y2) for(i=0; i<12; i+=1) { x1=200+110*sin(2*pi*(i)/12) y1=200-110*cos(2*pi*(i)/12) x2=200+125*sin(2*pi*(i)/12) y2=200-125*cos(2*pi*(i)/12) draw_line(x1,y1,x2,y2) }

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However ...Re: [Squeakland] Panel discussion: Can the AmericanMind be Opened?
by Tony Forster 03 Dec '07

03 Dec '07

> It would be interesting to > add more representations to Etoys, such as tally charts, rods, an > abacus, tesselating shapes, liquids: to see if they help children > become fluent in logarithms, polynomials, statistics, complex numbers > .......... like fluid mechanics, statistical mechanics, > Shrodinger's cat, cellular automata, developmental biology ..... The higher level representations above should not be added to Etoys but the primitives with which they can be created should all be there. See http://schoolgamemaker.rupert.id.au/samples3/ for examples of the kind of things referred to above. They would be very hard to create in Etoys because many of the primitives are missing. There are very few script trigger events, eg no collision triggers, and no bounce action to name but a few primitives which would make programming so much easier. For the kinds of things you might want to be able to implement in Etoys see http://curvebank.calstatela.edu/home/home.htm http://mathworld.wolfram.com/topics/AnimatedGIFs.html http://www.fi.uu.nl/wisweb/ Tony

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Re: [Squeakland] music and math
by mmille10＠comcast.net 01 Dec '07

01 Dec '07

Hi Alan. I think you're right about the character of music theory I had. I took two courses in it, both freshman level about 14 years ago. The first talked more about the history of music, and a little about structure. We learned about the different kinds of chords. I remember that much, though we didn't get into the mathematics, just characteristics. I guess there was some "subtle math" going on anyway, despite what was being taught, because we talked some about the patterns, and about how you can change a chord from one type to another just by making some adjustments in half steps and whole steps. The second course got more into "keyboard" harmony, as you put it. We learned about keys (ie. C major, etc.), identifying notes and chords by sound and making associations, learning "keyboarding" on a piano (doing scales and chords). The most interesting part to me was learning about the choral scheme. For the first time we discussed "music with constraints". We did a tad of composition, writing our own chords, using these constraints, and playing them. Most of what we did with this was analyze choral sheet music. Our professor wanted us to pick out certain characteristics. The only one I remember is key changes. It was interesting because I felt like it taught us about keys at a deeper level, and had us thinking "outside the box". It was the first time I had seen that the author didn't have to pay attention to the key markers at the beginning of each staff in order for the piece to hold together. I had seen this before in the orchestra classes I took in jr. high and high school, b ut I didn't understand what was going on. The writer could deviate into a new key by just manipulating some of the notes. Analyzing it felt like working with set theory. Once I hit a point where "Note X is not in the set of Key A", then I'd see if "Notes X, Y, Z" were in the set of another key. Sometimes I'd see that the new key the writer used was really a union between two key templates. I'm sure this confused some students, because they wouldn't see it as a change if most of the notes in the new key were the same as the old one. I believe it was in this context that the professor made the "mysterious" association between "good at math" and "good at music theory". No, I don't think he understood math and what it's about. What you said about music is very interesting. The idea that even the tuning scheme can be adjusted is news to me. I'm pretty sure we used the "equal tuning" scheme for everything when I had orchestra. Music theory showed me a little of the "mind" of the composer, but the way it was presented did not convey much of the math, except what us students could glean from the presentation. ---Mark mmille10(a)comcast.net -------------- Original message -------------- From: Alan Kay <alan.kay(a)vpri.org> Sounds as though the music teacher didn't understand math and what it is all about. (By "music theory" he probably meant the kinds of ("keyboard") harmony that are covered in the first year or two of college.) The kinds of thinking here are a lot like what is done in geometry. For example, one way to think of chords is as shapes whose "side lengths" are measured in semi-tone intervals (the smallest interval between two adjacent notes on a piano keyboard). These "distances" have been made uniform since the late 18th or early 19th century (not without musical penalty, see below). So a major chord in closed position has the shape 4-3 and a minor chord has the shape 3-4. So a chord of any kind can be built by starting on any note and counting intervals. This scheme normalizes chords in the same way triangles are normalized by their shapes. Scales are normalized in the same way, and thus this also normalizes keys. In harmonic theory, we are interested in how melodies can be harmonized by adding chords, how a sequence of chords (called a "chord pattern") "works" musically, how movements to other keys and returns can be made, etc. The first order and second order theories of these are very different. There is a famous 18th century piece by Purcell called "The Contest Between Melodie and Harmonie", and this sums up what Baroque music was all about. The golden age of Jazz (roughly, the 20th century until the late 50s or so) followed a very similar pathway in how melody and harmony were thought about (and not entirely by separate invention). The first order theory is very much about how tensions are introduced and relaxed, how the notion of a "key center" can be used to provide stability (and length) for excursions, how bass lines can be used to solid ify movements, etc. The second order theory was used very strongly by Bach then less so until roughly Wagner, and then in highly developed show and pop music (by stage bands, etc.) to try to intertwine melodic devices (like voice leading) with larger harmonic schemes that would force "emergent harmonizations" that are not easily described by the first order theory. What is called "chord substitution" (alternate harmonizations, sometimes of breathtaking beauty) in Jazz heavily rely on such mechanisms. "Mathematics" is a plural because it is about many different ways of "thinking very carefully" with invented representations and inference rules. So this kind of thinking about music is mathematics (i.e. rather than "like math", it is math). And, within music, there are lots of ways of making generalizations that help with styles. For example, my pipe organ and harpsichord have the older tuning schemes used in the 17th century. Why would anyone revert? Here 's the problem (as first discovered to their horror by the Pythagoreans). Octaves are multiples of 2. The harmonic 5th is the third harmonic, which is a multiple of 3. So if you try to make a scale by running out the 5ths (of 5ths etc.) they will never come back to the original note (2 and 3 are relatively prime). One way of running out the "circle of 5ths" creates a discrepency of about 1/75th of an octave. The equal tuning system mentioned above divides out this glitch evenly by making every 5th a little bit flat (and this results in rather wide 3rds). This works (sort of) OK on a piano because it doesn't have a lot of harmonics and most people are not very sensitive to in-tune-ness. Here, every chord is equally out of tune! On an organ or harpsichord (which are very rich in harmonics), the result of equal tuning is that major chords don't hold still, and minor chords are jangly. The older tuning schemes made some chords much more perfect and sacrificed others. This results in a harmonic theory that is partly about "sunlight" and "storms" depending on what keys you are playing in and how the harmonic progressions are devised. Because the harmonics are different on organs, harpsichords, clavichords, fortepianos, etc., it is not unusual for each to have a somewhat different unequal tuning to deal with the strengths and weaknesses provided. Some of the greatest music in the world was composed using these different bases for thinking, and much of this music loses much of its meaning in a modern tuning scheme. And, there is a math to these other ways of thinking about how things go together, but it is a somewhat different math. The analogy is to the many kinds of geometries - all mathematical - that have been devised starting in the 19th century. Referencing back to "art" and "technique". Learning all this doesn't necessarily make you into a composer or a better player, just as learning painting technique doesn't necessarily produce art. But if the artistic impulses are working then all this technique is tremendously helpful. Unfortunately for education, knowing technique is often all that is asked of a teacher .... oops! Cheers, Alan At 10:01 PM 11/28/2007, mmille10(a)comcast.net wrote: >Date: Tue, 27 Nov 2007 21:06:01 -0500 >From: "David T. Lewis" < lewis(a)mail.msen.com> >Subject: Re: However ...Re: [Squeakland] Panel discussion: Can the >AmericanMind be Opened? >To: subbukk < subbukk(a)gmail.com> >Message-ID: < 20071128020601.GA75166(a)shell.msen.com> >Content-Type: text/plain; charset=us-ascii > >On Mon, Nov 26, 2007 at 11:38:30PM +0530, subbukk wrote: >& gt; Coming from a culture steeped in oral tradition, I find 'sounds' better >> than 'symbols' when doing math 'in the head'. The way I learnt to handle >> numbers (thanks to my dad) is to think of them as a phrase. 324+648 would be >> sounded out like "three hundreds two tens and four and six hundreds and four >> tens and eight. three hundreds and six hundreds makes nine hundreds, two tens >> and four tens make six tens and four and eight makes one ten and two, giving >> me a total of nine hundreds seven tens and two". Subtraction was done using >> complements. So 93-25 would be sounded out as "five more to three tens, six >> tens more to nine tens and then three more, making a total of six tens and >> eight'. The technique works for any radix - 0x3c would be "three sixteens and >> twelve'. >> >> In Ind ia, many illiterate shopkeepers and waiters in village restaur ants use >> these techniques to total prices and hand out change. No written bills. >> >> The advantage with sounds is that tones/stress/volume can be used to decorate >> numbers. With pencil and paper, changing colors, sizes or weights would be >> impractical. > >Subbu, > >Thanks for sharing this. I think that it is very interesting that sound >and oral skills can be a basis for mathematical thinking. My cultural >background is less oral, so I did not even think of this as a possibility. >It seems that music and mathematics are somehow connected, but I never thought >to extend this to verbal types of music. > >Dave I took a couple music theory courses in college years ago. One of my professors mentioned that he noticed a correlation between those who were good at math and those who tended to grasp mus ic theory readily. He had no explanation for this though. ; ---Mark mmille10(a)comcast.net _______________________________________________ Squeakland mailing list Squeakland(a)squeakland.org http://squeakland.org/mailman/listinfo/squeakland

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Fwd: Re: [Squeakland] music and math
by Blake 01 Dec '07

01 Dec '07

> I took a couple music theory courses in college years ago. One of my > professors mentioned that he noticed a correlation between those who > were good at math and those who tended to grasp music theory readily. He > had no explanation for this though. I'm told IBM did a study trying to find a way to figure out the commonalities between great programmers (versus merely good ones) and the only thing it revealed was a slightly higher interest in music. Of course, music is a very mathematical thing.

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Am I the only one left ....
by Jim Ford 01 Dec '07

01 Dec '07

.... from the U.K. on this list? It's depressing to see all the interest and contributions from all over the world - except the U.K.. I guess that because the transition from the 19th to the 20th Century was so painful for us, having made it, we're reluctant to repeat the experience for the transition from the 20th to the 21st! It's particularly depressing that in spite of our Colonial history, the U.K. doesn't appear to be getting involved in the One Laptop per Child initiative. The school where I work as a Science Technician has a link to a school in South Africa. We are an independent (private/non-state) school with the students coming from well-off families, and I should imagine that a fund raising scheme to provide our link school with some laptops would be feasible. Unfortunately a major hurdle would be that the decision makers would be quite baffled by the XO laptop - 'How can it possibly be a computer if it doesn't run a version of Windows and MS Office?' - and I include the IT department in this attitude! I've spoken to the member of staff responsible for liason with the link school about the XO laptop, and whilst there was mild curiosity, they haven't reported back and don't appear to be following it up. Give me cause for some optimism someone - please! Jim Ford

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music and math
by mmille10＠comcast.net 01 Dec '07

01 Dec '07

>Date: Tue, 27 Nov 2007 21:06:01 -0500 >From: "David T. Lewis" <lewis(a)mail.msen.com> >Subject: Re: However ...Re: [Squeakland] Panel discussion: Can the >American Mind be Opened? >To: subbukk <subbukk(a)gmail.com> >Message-ID: <20071128020601.GA75166(a)shell.msen.com> >Content-Type: text/plain; charset=us-ascii > >On Mon, Nov 26, 2007 at 11:38:30PM +0530, subbukk wrote: >> Coming from a culture steeped in oral tradition, I find 'sounds' better >> than 'symbols' when doing math 'in the head'. The way I learnt to handle >> numbers (thanks to my dad) is to think of them as a phrase. 324+648 would be >> sounded out like "three hundreds two tens and four and six hundreds and four >> tens and eight. three hundreds and six hundreds makes nine hundreds, two tens >> and four tens make six tens and four and eight makes one ten and two, giving >> me a total of nine hundreds seven tens and two". Subtraction was done using >> complements. So 93-25 would be sounded out as "five more to three tens, six >> tens more to nine tens and then three more, making a total of six tens and >> eight'. The technique works for any radix - 0x3c would be "three sixteens and >> twelve'. >> >> In India, many illiterate shopkeepers and waiters in village restaurants use >> these techniques to total prices and hand out change. No written bills. >> >> The advantage with sounds is that tones/stress/volume can be used to decorate >> numbers. With pencil and paper, changing colors, sizes or weights would be >> impractical. > >Subbu, > >Thanks for sharing this. I think that it is very interesting that sound >and oral skills can be a basis for mathematical thinking. My cultural >background is less oral, so I did not even think of this as a possibility. >It seems that music and mathematics are somehow connected, but I never thought >to extend this to verbal types of music. > >Dave I took a couple music theory courses in college years ago. One of my professors mentioned that he noticed a correlation between those who were good at math and those who tended to grasp music theory readily. He had no explanation for this though. ---Mark mmille10(a)comcast.net

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