First Day of School

School is starting soon. In five days, I'll meet my new students. I'm not going to pass out a syllabus or go over classroom rules and procedures. Some teachers have to do that the first day, but I'm very happy to postpone all of that "boring" stuff to another day--some day less exciting than the first day! So, I usually start the year with some chemistry demonstrations. Here are a couple that I like to do on day #1:

Flammable Water

Of course, water isn't flammable, but I figure that my students need a "discrepant event" to get their brains going on day one. Before any students enter the room I place a few milliliters of Zippo liter fluid in an otherwise empty flask. After students arrive I'll ask the class if they think water is flammable. They'll wonder why their teacher asks such a ridiculous question. I'll then pick up the flask and turn on the faucet. (I have a sink at the front of the class; getting water directly out of the sink shows that I didn't do anything to the water--somehow they don't think much of the "empty" flask.) Since lighter fluid is less dense than water and since it doesn't mix with water, it will float to the top. I can then use my lighter to set the water on fire. If this year is like every other one, the students' eyebrows will all furrow and I'll have them right where I want them. Lots of directions it can go from there... :-)

Golden Rod Paper

The folks at Educational Innovations have some goldenrod colored paper that acts as an acid base indicator.  I take the golden paper and write a message to my students using a golden rod colored crayon. Usually before class I write something like "hi" and a smiley face. The message is invisible. Then I tape the paper to the white board at the front of the room and proudly announce to the class that I wrote them a little message. Students are perplexed since there is nothing apparent on the paper. Spraying (using a generic spray bottle from the dollar store) the paper with ammonia turns the paper red except where I wrote their message. Spraying again with vinegar changes the paper back to a golden color and makes the message invisible again.

If you're a chemistry teacher, hopefully those two demonstrations will give you a quick and easy way to get some students' attention.

En-Joy!