A story in School Library Journal highlights a new article which gives a different meaning to the term "Active Learning":

It’s long been known that movement helps people remember and retrieve information about an event or physical activity associated with action. But psychologist Susan Goldin-Meadow’s article, “Gesturing Gives Children New Ideas About Math,” is the first to show that gestures also help create new ideas.

“This study highlights the importance of motor learning even in nonmotor tasks, and suggests that we may be able to lay the foundation for new knowledge just by telling learners how to move their hands,” writes Goldin-Meadow in her article, now appearing in the current issue of the journal Psychological Science.

A little long for a tweet, but too short for a big post:

Students have trouble differentiating between what you tell them because you want them to know it, and what you tell them because you want them to do it.

So I was premature in declaring my blog "back". Turns out it my drupal installation had rotted a bit and some upgrades were necessary. Upgrades I didn't have time to install. Then an issue with mod_security...finally, operational again. Thanks Andy.

I'm glad to say that I'm back at work, both in cyber- and meatspace.

I had let the website malinger in the land of database connection error for a long time, and it turned out all I had to do was start it up again (the server on which it was running had been rebooted for maintenance).

Physically, I'm back in the office after a holiday vacation and a trip to Washington, DC for the annual Joint Meetings of the AMS and MAA.  I gave a fun talk about some of the courses I taught at Harvard using the Moore Method style. 

For months an online debate has raged about whether the new Linear Hadron Collider in Switzerland would create black holes that could "destroy the earth."

Well, the LHC is now online, and apparently, it has not destroyed the earth. Either that, or we're living in an episode of Lost.

I found this store on the NYU campus today:

After making more than one, the copies aren't unique any more. Sort of a strange business model, only selling one copy at a time.

I've been a fan of GeoGebra since I saw a demonstration of it by Markus Hohenwarter as MSRI last year. It's a free (open-source), cross-platform (Java-based), dynamical geometry and algebra application.

The nice part about being java-based is you can export your GeoGebra worksheets to html with embedded java applets. And then with a bit of parameter munging you can upload them to your blog. The embedded applet can be as function as the application itself (a nice advantage to being free; it can't be stolen so there's no barrier to making it completely available).

The nice part about being open-source is that people can contribute to it as much as they want. Now in the works is a tool to export a GeoGebra worksheet to PGF/TikZ, so you can put them in your LaTeX documents.

I just discovered that the Library of Congress has established a persistent URL (or "permalink") for every item in their catalog. The data in the link is taken from the item's Library of Congress Control Number (LCCN) and is therefore called an LCCN permalink.

I've been reading Steven Krantz's book How to Teach Mathematics lately, looking for some words of wisdom. One item has resurfaced during these Olympics.

All learning of significant knowledge requires considerable effort on the part of the learner. This fact has not changed since Euclid told Ptolemy (over 2000 years ago) that "There is no royal road to geometry."...

Go to any athletic facility and you will see young people spending hours perfecting their free throw or their skate board technique or their butterfly stroke. They don't hire tutors to achieve these goals...An eighteen-year-old understands clearly when an athletic coach says, "No pain, no gain." However, the same concept makes little sense to him in the context of mathematics or another deep academic subject.

I'm editing some text files, and I like to use subversion to do this. It helps with managing my own different revisions of the files, and can mark them automatically with metadata.