Waterboarding the Horse

Today I did a quick & simple demo of the activity series of metals. I had a solution of copper chloride. Metals that are more active than the copper ions in solution (such as aluminum) react, displacing the copper ions in solution. Metals that are less active than the copper ions (such as gold) do not react.

I poured the blue CuCl₂ solution into two beakers. Into the first one, I dropped a piece of aluminum foil. The aluminum dissolved impressively in front of their eyes, smoldering, fizzing, and heating up the beaker enough to create small clouds of water vapor (which many people mistakenly refer to as steam) coming out the top. After about a minute, the aluminum was completely gone, there was a pile of copper metal at the bottom of the beaker, and the solution had turned from blue (copper chloride) to clear (aluminum chloride).

After the fizzing and sizzling was finished, I took off my gold wedding ring and dropped it into the other beaker of copper chloride…

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Every teacher has at least one kid who needs the teacher’s attention for every minute of every class. Often, those are kids I really enjoy having in class, as long as they have a sense of where the line is and don’t cross it. I had one two years ago, S., who took his chair apart during one memorable class.

The one I have this year is G. He’s fully aware of what he’s doing, he doesn’t do it out of malice, and I can usually keep him on track enough that his comments help move the class forward, at least most of the time. And I make a point of genuinely showing my appreciation for his enthusiasm when appropriate.

Today, G. showed up in one of my other chem classes (a different section of the same class he’s in). He participated in the class, and joined in the group activity as if this had been his regular class, so I didn’t think much of it. (I wondered at the time whether he was getting dismissed early and was attending a different class on his free period so he wouldn’t miss anything–he had been absent the previous day.) Then I saw him again in his regular class two periods later, so I asked him about it. Evidently, he just felt like joining one of my classes during his free period.

Whatever his motivation, I took it as quite a compliment that he decided to spend his free period in a chemistry class.

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When I found out that I wasn’t going to be teaching in Peabody next year, one of my favorite students (yeah, I know, we’re not supposed to have favorites) asked if there was anything she could do. Knowing that this student is an exceptional writer, I asked her if she would write a recommendation for me, from a student’s perspective.

I received the recommendation in my email today. This is the text of it.

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I got a nice comment from one of the students in my organic chem class yesterday. She had visited Boston College and looked over several of the problem sets & answers for their intro organic chem class. She made a point of looking at problems from different parts of the course—beginning, middle and end—and was psyched that she had been able to understand and follow just about everything on all of them.

I’ve had several occasions throughout the year to fret about my inability to teach organic chem in a way that’s neither too simplistic nor too difficult for high school kids (albeit most of whom are in the top 5% of their class), and I didn’t feel like I had gotten the level about right until after February vacation. So it was especially nice to be measured against one of the college courses that I’m trying to be comparable to and actually compare favorably.

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