All that and an ice storm, too!
I started the day cleaning out three dozen beakers which had held hand soap, corn syrup, and canola oil. I'm having the seventh graders measure the mass and volume of different quantities of different liquids, to prove that density is the same for a particular substance no matter how much or how little you have. They didn't finish on Tuesday, and I didn't see them on Wednesday, and I did not get a chance to clean out the beakers until today (my kingdom for a lab assistant!). Soapsuds everywhere. Me on my knees by the artroom sink, which is designed for 3-foot-tall people to wash their hands in. Corn syrup is tenaciously sticky.
Fully half of the seventh graders did not turn in a first draft of their lab reports, which were assigned on Monday. Excuses ranged from "I left my backpack at home" (WTF?) to "my computer has a virus and I did it but I can't get it to school" (your computer has had a virus for months - even I know that - why would you even try to type your project?). I turned into evil-Mussolini-wicked witch-teacher-from-hell. This happens often with this class. I resolve to be more patient with them, to be nicer to them, but then I enter the classroom and it's something new every day, and I end up back in dictator-land. That's the only way we get anything done. The first drafts I've read so far are pretty good, though, so maybe we are starting to make some progress. And they were quite impressed when we poured all three liquids into one beaker and they formed very nice layers by density!
I was supposed to call the homes of all the students who didn't turn in their projects - I assured the kids that I would - but the office where we store contact info was locked by the time I was done with robotics and ready to turn to that project. So now I'm going to look like I am not good for my word, and they will think they can "get over" on me. Urgh. Not like I was looking forward to calling twelve kids' parents, but I needed to do it because I said I would.
Newton's Laws have really brought out the inquisitive side of my sixth graders. It's wonderful - they are asking good questions - but I still have to say, "Okay, that's enough for right now, we must go on, I'd like to teach the lesson I planned but I'll take more questions later." It's great to have kids posing thought experiments about friction-less worlds. One reason I wish I had a mentor is that I am having a hard time explaining or demonstrating to the kids why it is that slowing down is essentially acceleration in the opposite direction of the object's motion. I understand it, but I can't explain it to my mostly-concrete thinkers in a way that makes sense to them.
And here's another puzzle. I introduced the idea of the normal force - when you push against the floor or wall or an object, it pushes back on you - and the kids seem to get it. At least, they know when to draw it in force diagrams and the like. But one class today hit an existential wall: they just don't believe in it. And the truth is, I hate, "You'll just have to believe me on this one," but I don't really have a better answer. Help me out, readers - where does the normal force come from? How do I prove it to my sixth graders? What I tried today, which convinced some but not all, was pointing out that if you were to kick a bowling ball, it would really hurt your foot. Why? Because your foot applies a force to the ball, and the ball applies a force back, which causes you pain. And the harder you kick the ball, the more it hurts, because the ball "kicks back" just as hard. They liked this example, but some kids insisted that the pain in your foot comes from the fact that your foot hit the ball, period. No "normal force" needed to explain that! Similarly, walls don't fall over when you lean against them because they're walls - of course they don't fall over. I guess that's why it's called "normal" - it feels so obvious, we don't notice it. Help!
We focused on Newton's 2nd law today. I talked to them about the relationships between force, mass, and acceleration, and we went over several examples. Then I introduced the formula - F=ma - and a second version of it, a=F/m. I explained that these are two different versions of the same formula, and that they might understand it now but they would definitely understand why when they did algebra in a year or two. Then we did some practice examples, which they found very easy. In two out of three classes, kids raised their hands and asked, "But what if you want to find the mass?" So, I gave them an example problem and asked them to think about what the formula might be to find mass. In both classes, hands shot up and they figured it out! I had them give themselves a hand for having done algebra (I am always trying to de-mystify the "scary" parts of math & science, which are often the most lovely once you try them). I think they were really proud of themselves.
And then I spent ten minutes back in dictator-witch mode, when my last class of the day not only did not follow our school's hallway behavior rules, but then became quite resistant and difficult when I enforced them. It was another of those, "Show them who's boss" moments and very stressful, but at this point, I know how to do it. Luckily, once class started, they settled down, I settled down, and they proved to be the most inquisitive of all the classes. One girl, who is consistently very difficult to deal with, in part because she is very bright, spent the whole period complaining loudly about a headache - a headache which developed coincidentally just after I asked her to follow the same rules that everyone else follows.
I will post about robotics separately so those following that story can find it easily - but the crowning moment of the day was when I was lining up the robotics kids to go downstairs, and they were just starting to settle down, when a little mouse ran squirmingly along the base of the cabinets just a yard or so from my toes! I am not a shrieker, but I gave a little "Eek!" I gave out the rest of the Hershey's Kisses that I've been using (sparingly) as
So today was a little of this and a little of that.