Tuesday, November 24, 2009

I'm now the proud owner of a Screencast.com Pro account.  Here's one way I use it:


Tuesday, November 3, 2009

Screencasting in Sound and Music

Next semester I'm teaching PHYS 1140 Physics of Sound and Music which is a course for non-science majors.  I plan to use the same organizational structure that I did in last year's Modern Physics course.  I'm a little nervous about being able to motivate the students to put in the time outside of class but I really think it'll pay off for them (and me) if I can make the class time useful for all of us.  I have two ideas for that.

First I'm going to try to do a demo in every class.  That's going to take some planning but luckily I have all of j-term free (with the exception of chairing the tenure and promotion committee) to do that so I think there's a chance I can pull it off.  Since the screencasts and the book will be taking care of the material I think it'll be fun to start each class (after the quiz, of course) with a demo and then have the students talk about the physics it represents.  I'm sure there will be some days when I'll be lazy and use a computer simulation instead but even those can be pedagogically useful (in fact I've recently read an article that makes the case that the cleaner simulations do a better job of teaching but that's another blog post).

Second I'm going to try to emulate Google's Moderator software with the questions students post.  That way the class can "crowdsource" the questions and rank the best ones.  That way it'll be ok if I don't get to every question from every student.  I've got some work ahead of me to pull that off but I've done something similar in the past so hopefully I can get it done in time.

Sunday, November 1, 2009

leaf evidence

leaf update

It appears that one lawn bag holds between 40,000 and 50,000 leaves. The boys have renegotiated for $1/bag from now on. They're not dumb, those two. here's the description of the project

Leaf math

The leaves have definitely fallen and I'm going to have my kids do some counting for money. I figure $1 for every 100,000 leaves should do the trick. Of course, it only counts if they get the leaves in the bags!

So how do they do it? Powers of ten, that's how!

First I have them each make a pile of 100 leaves. Then I have them make a new pile that seems the same size. If that one ends up within 5% of 100, I approve it and then they make 10 piles of 100 leaves. Then they gather that together and take a good look at how big that is. Then they make 9 more such piles and look at what 10,000 leaves look like. Then they make 10 piles of those to see what one dollar looks like. My guess is that one of those paper garden leaf bags will hold somewhere around a dollar's worth. For my yard that'll mean no more than $10-$15 out of my pocket, a clean yard, and kids who can brag to their teachers that they counted to a million over the weekend.