Eclipses

[asterroc]

Like any good researcher, when I noticed students responding a certain way to a free response question, I tried to tabulate what they all said, and turned it into multiple choice. Basically, the students were trying to describe why we don't have solar and lunar eclipses every month. The drawings below are based on the word descriptions from the students. And I wanna know what you think: which picture is the main reason why we don't have solar and lunar eclipses every month?

Descriptions in words:
A) "The Moon is in a different plane."
B) "The Moon's axis is tilted."
c) "The Moon goes above and below."
D) "The Moon's orbit isn't a perfect circle."
E) "The Moon's orbit is tilted."



[Poll #1956047]

Comments

[hitchhiker.livejournal.com]

done. nice question; not something one usually thinks about.

[zandperl.livejournal.com]

The specific assignment on the lab had the students first predict in a simple (flat) model how often eclipses would occur. Then said that they really occur approximately every 6 months, so how could they alter their model to account for that. It asked them to explain the modification two different ways: in a classroom model with a ping pong ball/their heads/flashlight, and also in space with the actual Moon/Earth/Sun.

I walked around the class to help with this, which is probably why 50% did have it correct. Honestly, I'm not sure how many of the answers that I marked as incorrect are (1) the student really thinks the wrong thing is true, (2) the student conflates a few things, or (3) the student thinks the right thing is true but expressed it poorly.

Relatedly, read an article this evening (Karplus, 1977, "Science Teaching and The Development of Reasoning") which described Piaget's ideas of concrete vs. formal thinking in language closer to the modern idea of novice vs. expert thinking in the sciences. Some days the articles I read in my studies just blow my mind. Other days they're really boring b/c they just restate things I already knew. This was one that took things I already knew and put it into a new perspective that gives what I already knew so much more meaning. :) I think having just graded this lab yesterday and today also helped, as I could relate this article to a specific case - that is, I needed to do concrete thinking about it! :-P I'm definitely still a novice in AER.

[hitchhiker.livejournal.com]

interesting paper, though i suspect that i didn't really get much out of it since i'm not familiar with piaget's theories. but it's always interesting to get a glimpse of someone else's field :)

[zandperl.livejournal.com]

Yeah, that's an unusual paper because it's basically a lit review of one paper: taking Piaget's ideas which are usually looked at in the context of early childhood development and child psychology, and translating them into the language of high school science education. I'm not very familiar with Piaget's theory for exactly that reason: I've never seen it applied to older children, college age students, or adult learners, and while Karplus is applying it to older children, it's still really relevant to what I see in the classroom at the college level.

But yeah, I like it when something I read in science ed makes me go "whoah..." There's this image that education research is "easy", so it always makes me happy when I get the same sort of "ah hah!" moments that I get when solving a difficult astrophysics problem. If Ed were easy, then I'd never need ah-hah's because I'd never be at that stuck moment you get right before the ah-hah.