Monday, January 22, 2007

Three bicycle stories

Cross Training
This is the (academic) year I made the commitment to become a bicycle commuter. I've been riding daily since the start of the academic year, and what do I have to show for it? Well, in the past, when I went skiing, I felt it in all my muscles -- especially in my quads. This year? I can ski all day and not even feel it. I'm almost as fresh at the end of the day as at the beginning.
"Learn how to drive!"
I had my first run-in with an asshole driver today. (Which is pretty good, given the time I've been commuting by bike, and probably says something about driver courtesy in this area.) He wanted to change lanes and seemed to take exception to the fact that I was already in that lane, and ahead of him. He showed his lack of originality with the aforementioned quote. You guessed it; he was driving a pickup truck.
The curve approaches
Sand on the ground and my speed
Hazardous mixture

Friday, January 19, 2007

Math Education: An Inconvenient Truth

A little over two years ago, in a posting comparing schools here in the Seattle suburbs with those in the Gainesville, Florida area, I wrote, "... Northshore uses the Everyday Math textbooks, while Alachua uses Harcourt Math. Both series are, in our opinion, excellent." That was from my wife's and my points of view as parents of a second-grader, with whom we work outside of school on supplementary math and other subjects. As the YouTube video linked from the subject line above indicates, our assessment probably isn't reflective of the full K-8 experience of most families.

First off, go right now and watch the video; it's excellent. Seriously, watch it.

My opinion of Everyday Math was based on two of its aspects:

  1. Because of its spiral approach, it introduces algebraic concepts very early and at a level that seemed appropriate for those children.
  2. It has some very interesting ways of teaching concepts such a addition and subtraction that seem, to me, to make their relationship as inverse operations intuitively obvious. Again, a more advanced concept introduced in what seemed an age-appropriate manner.
It is important to keep in mind that this was coming from a parent of a child who was far ahead of her grade level in math (not to brag, but as a fourth-grader, she is doing seventh-grade math) and who did extra work at home. The YouTube video points out some matters that have become much clearer as time has passed and my children have worked with math textbooks in higher grades.
  • There's not much practice in the textbook. This is offset by extra materials used by teachers in our school here (such as Mad Minute), and by our own use of the Singapore Math books.
  • There's all sorts of irrelevant materials in the textbook. A chapter on patterns has a page on Native American crafts, but that page says nothing about the patterns in those crafts. It's basically a generic, too-brief overview of such crafts. Certainly, there is a strong connection between weaving and patterns, but nothing is said about that there. We fix this ourselves by talking about such issues.
  • Exercises at the end of sections are a mish-mash of all sorts of problems. On the one hand, review is good. But why have the first problems in a section of a late elementary or early middle school textbook be a series of very simple addition or subtraction problems? It distracts the child from the topic just learned, and makes her wonder if maybe there isn't some sort of trick involved and those problems aren't as easy they seem. It could have made her less secure about her math ability! (Actually, by this point, our older daughter is quite cynical about these "baby problems" and isn't bothered by them.)
  • It has all sorts of bizarre approaches, such as those detailed in the YouTube video (did I mention that you should really watch it?). Stuff which leaves me wondering if the authors were on peyote when they wrote that section. For our daughters, these are just random and interesting things, and they rightly dismiss them as inefficient and confusing. They ask their teachers if they have to do it that way, and do so for the few problems where it's required, reverting back the much more efficient, standard algorithms they are familiar with.
As a Computer Science professor, my observation is that I can see the effect of this approach to education. At the end of my third week teaching freshman calculus (I plan to blog about that shortly), I have noted that the de-emphasis of topics such as division of fractions impacts college-level math. Unfortunately, we're on the quarter system here, and so there's not much leeway to address these issues in class. However, I am making a mental note for myself to discuss this with our Quantitative Skills Center folks; maybe a review of K-12 textbook content would provide some ideas for remediation. In the final analysis, that is what these textbooks have done: pushed topics they think too time-consuming into university education time.

Additional Links: Reviews of UCSMP Everyday Mathematics, Where's the Math?, Donald Simanek's documents and links on education.

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Wednesday, January 03, 2007

The last syllabus you'll ever need

Over at Halfway There, Zeno has a post about a one-size-fits-all syllabus. It certainly is the case that course syllabi have evolved from a means of clear communication with students to written contracts on the nature of courses. Perhaps we should take a page from software End User License writers, who typically tell us we have no rights and that they can change the contract anytime they want and that a post on some web page we'll never check shall be considered sufficient notice of such change.

Oh, well, I guess I'm not curmudgeonly enough yet to do this. But, if I'm told one more time that my use of the word "should" in a homework assignment can be reasonably interpreted as advice, rather than a requirement...

P.S. If you're a student reading this, I hope you realize it is in jest. I am well-known for my voluminous syllabi. The next best thing to a captive listening audience is a captive group of readers.

Tuesday, January 02, 2007


I've been along time user of the NewsFire RSS reader. Unfortunately, newer versions require OS X 10.4, and I have delayed upgrading my machines long enough that I'm just waiting for 10.5. Additionally, NewsFire is just incredibly slow (at least, the older version I can use) and crashes frequently. It might have something to do with the 360 or so feeds I track.

Anyway, I've left all my troubles behind, now that I've adopted the Vienna RSS reader. Fast and reliable. And free.

Monday, January 01, 2007

Roll your own syndication

I generally try to make my course web pages act as web portals for the course, with all the information students need (except, of course, for the pearls of wisdom contained in their textbooks and my lectures) there. I've also been increasing my use of blogs (and now, podcasts). Therein lies my desire to syndicate RSS feeds onto my web pages. Previously, I had been using (there are other similar services), which provides the ability to includes JavaScript on your web page that will generate customizable HTML summarizes from RSS feeds. The problem I had with this was increased page load time: I was dependent on responses from their server. Now, I've found a new tool that works much better: RSS2HTML, which is a free PHP script that generates HTML according to a template that you write. There are three ways that I've been using it:

  1. As a "complete web page generator". I use the PHP script, customized to hard-code the RSS feed and template file URLs, as my web page (for example, renamed as "index.php"). This is useful when the only feature available to you on your web site is PHP script execution.
  2. As a server-side include. For example, the SSI code on one of my course pages will cause the PHP script to generate suitable HTML to be included for the course blog's RSS feed. The template file here is just an HTML snippet. This requires both PHP script and SSI support on the web server.
  3. The third approach is what I'm using as of this date for the list of upcoming conference deadlines I place in this blog's sidebar. In this case, I can't make use of either local PHP scripts or SSI, as Blogger doesn't support them. So, I rolled my own RSS to JavaScript service by placing a modified rss2html.php script on another server, and use it to generate JavaScript output, rather than HTML (the script doesn't care what's in the template, other than the variables that it replaces with feed information). So, the template contains lines like:
    document.writeln('  ~~~ItemDescription~~~');
    There was one problem: the RSS fields can contain single quotes, which will of course screw up the generated JavaScript. To fix this, the PHP script must be modified. Specifically, lines like these:
    $this->ItemTitle[] = trim($this->title);
    $this->ItemDescription[] = trim($this->description)
    must be replaced with lines like these:
    $this->ItemTitle[] = str_replace("'", "’", trim($this->title));
    $this->ItemDescription[] = str_replace("'", "’", trim($this->description));
    This will replace single quotes with HTML entities that display as quotes but won't act to close the strings in the document.write() calls.

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