homework – Composite

The elusive kilogram!

April 15, 2009 Liz

Last night I had this conversation with Moomin. “I just want to make sure you actually understand this metric system stuff rather than doing the problems blindly. So let’s draw a little chart. How many grams in a kilogram?” “Um… ummm… ummmmmm…. Oh yeah! 1000!” “Okay, how many centigrams in a kilogram?” “There’s no such thing as a centigram.” “There is!” “No there’s not! They didn’t tell us that! Look, I wrote it down… Can you just let me finish this page? It’s my bedtime!” Bedtime is not a good time to explain the entire concept of the metric system so I gave in.

Later a certain person assured me that Moomin was right! Well, they are wrong! 8-P

And then led me into a delightfully pointless reading: Wikipedia: Kilogram.

The kilogram is the only unit not defined off a physical constant – it’s defined from this particular object, the 130-year-old International Prototype Kilogram or IPK. And a whole bunch of other metric units are defined using mass, like newtons, pascals, joules, amperes, couloumbs, volts, teslas, webers, candelas, lumens, and lux. (The plural is not “luxes”. I looked it up.) It was created and then defined as the standard. But some replicas of it were created, like the Kilogram of the Archives, and over time they have diverged from each other. The story of what they’re all made of, and how they’re periodically compared and verified, is pretty cool. And sort of insane. Is that a whole bunch of people’s life work? Making sure that we know how wrong our kilograms might be? Eeeeeee! That’s so hot!!!!!!

And so are multiple bell jars over a brass-looking pedestal thingie! It’s like The International Geek Thingamajig on a Steampunk Cake Stand of Awesome!

Burrow deeply into the kilogram article and you will get to the proposed alternatives that would tie the kilogram to a constant. Atom-counting approaches (I liked the Avogadro project, which would use a silicon sphere); Ion accumulation; and the rather sexy sounding watt balance method: the electronic kilogram!

I am tempted to show all this to Moomin but not until he finishes today’s tedious homework, which is three pages of textbook problems of temperature conversion. No one needs that many examples – it is very pointless. At the least I will wow him with the revelation that there are exagrams, zettagrams, yoctograms, and zeptagrams which I will prove through the irrefutability of Wikipedia because we all know the important thing to teach 4th graders is that Wikipedia is totally true.

Being naughty for the substitute

September 30, 2008 Liz

“Our substitute teacher showed me a way to say something isn’t equal,” Moomin told me today as he did his homework. “See?” and with vast satisfaction he wrote ≠ on his worksheet.

When I asked him how the sub was, he said she was pretty good. “Mom, I have to tell you I’ve noticed something. In books, people are a *lot naughtier* with substitute teachers than they are in real life.”

We discussed this a while. Tacks on chairs! Elaborate tricks! And when have you ever seen this happen? I haven’t. It seemed so alluring, like midnight feasts in boarding school novels. Twins also have much better adventures in books when they switch places than they do in real life. Why do some people seem to think it’s a good idea to write books that are basically training manuals to teach kids how to be extremely naughty. I wonder if Moomin will think over that idea – the question of why you would write a whole book about kids being extremely naughty? Are they training you to be BAD? He found this hilarious, and appeared to be thinking it over.

What about books where horrible things happen to kids? A friend of mine recently claimed, there are just a lot of twisted people who want to write horrible books about horrible things happening to kids? I thought of her theory tonight at bedtime, as we began reading Harry Potter and I wondered how Moomin would react to the Series of Unfortunate Events. He is maybe not quite cynical enough to enjoy them.

Well, back to the homework. Tonight’s homework took us less than half an hour. It was a bunch of not very exciting worksheets, which surprised me since this school is supposedly all about the non-worksheet-doing, but it may be an NCLB thing and they just *have to*.

I told Moomin I would be his “speed coach”. He faced this prospect with good cheer. At first he didn’t want me to say anything; “I know, I know, I can do it, I know how to do this!” but I asked him to pause and listen first. So, first, look it over and think what is on the whole page, and give a thought to how long it might take. It looked like a 2-minute worksheet to me, with some stuff about homophones and spelling words. So I set a little kitchen timer, an egg timer with a dial that ticks, and sat across the table reading a magazine a little while watching his progress. Whenever he got all stuck, I reminded him to skip it and move on. At just about the 2-minute mark I said he was doing well but that it was clearly a 3-minute worksheet, and dialed up another minute. Hey! Done! He is quite fast. I encouraged him to cross out finished answers (quickly without precison) and skip ones if he was not quite sure; and if he made a mistake and then catches it — for example writing an i instead of an e in a word – try to remember not to erase an entire word or line, but just write the e over the i a couple of times hard with the pencil.

It’s just like the authors who teach naughtiness! I have to encourage Moomin not to be perfectionist in his work, and not to mind being a bit of a slob. Lucky Moomin — there’s no one better to teach slovenly habits than his good old mom.

The next worksheet took 2 minutes. Then we did another one. Booooring! So much better to get it done quickly if it’s going to be that boring?

We moved on to math. More worksheets. They were things like (17 + 15) – (8 + 3) = ?? The problems were all crammed together with no room to do the working out. Moomin wanted to draw lines from each set of parentheses, one from the 17 and one from the 15, pointing together in a triangle, and then the minus sign, and then the other bit… I persuaded him it would be faster and less cluttered to jot the answer to 17+15 just above it. (Even though it was horribly crammed in.) And then the other bit, and put in the minus sign to remind yourself what you’re doing. Then the answer!

That went much faster.

There were a few unboring problems. One was: Glenn has 6 more books than Bob. Bob has 4 less books than Susan. Susan has 10 books. How many books does Glenn have? He worked it out very nicely with just a hint from me. Not for the first time, I thought to myself that he will really enjoy algebra and geometry.

After homework was done I showed him a book of math puzzles, which he enjoyed until he realized I was sort of tricking him into some kind of Learning Experiment when he would rather be reading his latest Dragonology book.

I think back to the times when I worked as a tutor. I was good at getting people quickly to the point where they realized they didn’t need a tutor, but could figure things out for themselves. It was mostly about teaching ways to think, or ways to approach a problem or a task, and of course, self-confidence.

When I need tutoring, it’s more or less the same. I get stuck on some bit of debugging and begin to doubt myself, or I need help breaking a big task down into stuff I can understand. It’s good to keep my own feelings in mind as I help out another person.