The safety information is below.
The longer term plan includes having students create things a little like this:
To figure out how to do class-based video production, I’ve started the first one and we’ll work together as a class to make a copy with subtitles that describes ( but does not explain) what happens. The original, without the descriptive subtitles, can then be used by other classrooms to puzzle over the demonstration.
They too can create a careful description and check it against their initial explanation. Almost everyone has an initial explanation that fails to correctly explain the order of observed events.
I’ve spent an absurdly long time processing this demonstration, and I hope it is ultimately worthwhile. As I see it, understanding the underlying science is required to understand convection and that understanding convection is required to understand an incredible amount of Earth science. Understanding a bit about fire is also helpful for understanding quite a bit more about Earth processes.
I’ll admit the production values need a little work.
Later this week, I plan to post #2: A Water (Vapor) Balloon: What happens when you microwave a sealed balloon with just a few drops of water in it?
SAFETY AND OTHER IMPORTANT INFORMATION FOR THE GLASS ON THE FACE DEMONSTRATION:
I have burned myself in two different ways doing this demonstration:
1. Holding the glass on its side or at an angle before placing it against my cheek. DON’T DO THAT!!! This allowed the upper rim of the glass to heat up and that created a semi-circular burn on my cheek.
2. I used too large a piece of paper and consequently had a large flame licking my cheek. DON’T DO THAT EITHER! That was really just stupid on my part.
I am sure there are a number of other ways to injure yourself when you play with fire in this way. Be smart. Be careful. Where eye protection.
OTHER TIPS:
- Teachers should spend time processing the demonstration. Too many science demonstrations are dealt with too quickly. Kids may think it’s cool, but they should also figure out what’s going on. Please don’t simply tell them. (Note too that I haven’t told you why this does what it does).
- Newspaper burns better than paper intended for the copy machine or printer. And it’s cheaper.
- The glass needs to be clear and clean so people can see what’s going on. Wash it after a few uses to keep it clear.
- The glass needs to be glass so it won’t melt.
- Razor stubble makes it so the glass won’t stick. Shave shortly before the demonstration (if your face requires it).
- Tik Liem, who I saw do this years ago at a STANYS conference, put the glass on his forehead. I’ve never had my hair short enough to do that.
- If you leave the glass on, it will leave a hicky, according to Liem. I trusted him on this and have never left it on for very long.
- You may know that accupuncturists do stuff like this as part of therapy. I don’t have any real sense if such things have any health benefit. (That’s more an aside than a tip, I suppose.)
And, on a completely different note, I’ve added some folks to my blogroll. Take a look at what Joe and Melisa have to say.
By: 
