Hectic days make light blogging
Wed 30 Sep 2009 05:59 PM
When I have teach logic to one or two hundred students, the class is in one the university's lecture centers. All the LCs have digital projectors, so I can put up tables and charts as needed. Mostly I work through examples which I adapt on the fly, however, so I use the board.
The old lecture centers, which I have used in the past, have actual chalkboards. Admittedly, the fluorescent strip lights over the chalkboards do not all work. Some have graffiti recording the date many years ago when they broke down: no mere dead bulb, but bent and twisted fixtures.
This semester, I'm in a lecture center with new whiteboards and strip lights. The functioning lights make it feel less like a post-apocalyptic movie from the 70s, but I hate the whiteboards. To be precise, I hate whiteboard markers. There is no way to tell by looking at one whether it will write well enough to be seen at the back of the room. It is not enough to test it as I leave the office, either, because a marker that is just fine now may go all ghostly after a few lines of scribbling.
Yesterday, both of the markers I brought went wispy. So I sent my TA back to department to fetch more and muddled along until he got back. He handed me two black markers. One was a whiteboard marker, which got me through the rest of the hour. The other was a permanent marker that had been in the drawer of office supplies. He was in a hurry and grabbed the markers that he could find, and luckily I noticed - but that could have gone horribly wrong. My examples are not so witty that I want them to be tattooed on the board for the weeks it woudl take for someone to come in with marker solvent.
So I have a strong preference for the old lecture centers, with their dysfunctional lights and their chalkboards. There is a wonderful practicality about chalk. I can grab a few pieces on my way to lecture and be sure that they'll write for the whole class period. And each piece of chalk fails gracefully - rather than continuing to make spectral marks long after it's effectively dead, a nub of chalk will produce readable white lines until it is too short to hold.
Some people complain about chalk dust, which admittedly gets all over the place. I get it on my hands over the course of lecture, and from my hands it finds its way to my shirt and pants - but it washes off easily. Although whiteboard markers don't always end up on my hands and clothes, when they do it's a bad scene.
And whiteboard markers use up ink and solvent, leaving behind their plastic carcasses. So chalk is more eco-friendly. Even the boards are green.*
This all makes me feel like a curmudgeon. Should I have waited until tenure before getting so crotchety?
* This is a joke, but I suspect that chalk is less resource intensive. If you actually know about this, say something in the comments.
Thu 01 Oct 2009 07:41 AM
You know, you can draw over permanent marker on a whiteboard with an actual whiteboard marker. The whiteboard solvent will dissolve the permanent marker ink. Then you can erase it. That is, of course, assuming you have a working whiteboard marker as well as the permanent marker.