Posted by: thediygeochemist | April 12, 2009

expectation values and science mysteries

Since I’ve made it through the admissions obstacle course but haven’t started grad school, I have the luxury of being able to post about nothing but trivialities.

I homeschooled my kids for ten years or so; after a transition period of two years, my husband took over. It’s interesting to see how different our approaches are. For example, my husband takes a decidedly practical approach towards education: he’s been known to have the kids put aside their history/math/whatever to look at an offer he received in the mail. “What’s the catch?” he’ll ask, as he hands them a letter screaming, “YOU HAVE WON A TRIP TO THE BAHAMAS!”

One day, he handed them a sweepstakes entry and asked them if it was worth it for him to send it in. So they calculated the approximate amount they could expect to win: $1 million grand prize, 1 in 20 million chance is worth .05 to us, etc. The total value was something like 9 cents, less than the cost of the postage stamp. Needless to say, they advised my husband not to send in the entry.

I told the boys that what they’d just done was calculate an expectation value, that they could expect to do similar calculations in physics, chemistry, or statistics. I thought it was cool that my husband thought of that little exercise; I never would have.

What I did a lot of, when I was still the primary educator, was have my kids solve science mysteries. Like the time I dragged them out to the back yard to see the trunk of the yucca tree I was chopping down. This was a huge task; I’d chopped two of the main branches a week prior, and the other two main branches just a day or so before.

The trunk was still untouched. It was wet on one side, and dry on the other. “Why?” I asked. Maybe the neighbors had been watering the garden and had sprayed it through the fence, they suggested. But no, because the wet side faced away from the neighbors’ yard. Maybe I had been watering the garden? No; the garden was bone dry.

The discussion went back and forth, and finally they figured out that the roots/xylem were still pumping water up to the non-existent branches. But–why was the tree only wet on one side? My oldest son finally figured out that the dry side was the side with the branches I’d cut off a week earlier; the scars had “healed” so that no water was leaking out. But the branches I’d cut off the day before were oozing copious amounts of water.

I still sometimes dig up science mysteries for my kids. But when I don’t find the time to do that, I know that they’re learning about all sorts of other useful things. In short, the responsibility swap has been a good thing, and will make my boys more well-rounded in the long run.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s


%d bloggers like this: