So when we got back, we actually had a "side demo" first. He talked a bit about air resistance, then dropped coffee filters & asked which would hit first, the single one or the double one. (It was the double.) Could we figure out this relationship? This is the process of science! 1) Ask a question. 2) Collect data. 3) Organize & analyze data. 4) Draw conclusion. 5) Make a mental model -- with predictive power! 6) Use the model, & adjust when needed. So that's a nice little wrap up, before the workshop is over.
But then we got back to those poor stick people jumping (or skateboarding) off the building. Don did a demo in the hallway (that'll take me a long time to get right) where he dropped one golf ball straight down & threw the other out to the side. We listened & heard them hit at the same time, even when he barely gave the sideways ball any oomph. Then he asked what happens if you angle the sideways ball up (it hits later) or down (it hits earlier). You could do this demo with ping pong balls if you were worried about breaking stuff -- It'll just take practice. So that's a great demo of what would happen to the stick people & a good way to introduce the dissociation of sideways movement from downways movement.
Then he had us watch a video of a ball being thrown across the screen (http://gpschools.schoolwires.net/Page/1780, at the very top). He had a volunteer put a sticky note at every location of the ball when it was slowed down to single frames. Who's our friend? Symmetry! & the horizontal spacing looked pretty equal so the sideways velocity had to be constant. What shape is it? A parabola! All projectiles fly in parabolas (except that my notes say "all projectiles fly in projectiles", sheesh). So we wrote out that the horizontal motion had constant velocity & the appropriate formula & that the vertical motion has constant acceleration (free fall, remember?) & the formula for that, & then we were set loose on worksheet #1. (This was the math-iest thing we've done so far.)
Also, Perfect Pic is an app that will slow down any video to 20 frames per second -- I'm not sure if this is what Don't video used but a person in my next group had it for her iPad & it was pretty useful. We'll see if it's available for Android devices (& if it's free). I can't find it right now so I might have to do more digging...
Then we had to draw a motion map by second & to scale of somebody dropping a ball from 40 meters off the ground. The key here is that the velocity & acceleration arrows don't have to be proportional to the distances.
Then we worked on worksheet #2 for a while & then we moved directly into the challenge -- trying to bounce a steelie off of a cup on the floor. We had to use a ramp down to the track. My groupmates did most of the work & they didn't put it on a whiteboard. (They were really into the challenge.)
We had a second challenge, where people could choose either group -- either shoot a ball so that it knocked a cup over on a table (at the same height it was launched from) or shoot a ball & knock over a cup on the floor. I wouldn't use those launchers anywhere near glass but they were fun. I was in the symmetrical group & we got close but no cigar.
We did have a reading for this unit -- 5 Practices for Orchestrating Productive Task-based Discussions in Science (http://www.nsta.org/store/product_detail.aspx?id=10.2505/9780873537452). (The math version, http://www.amazon.com/Practices-Orchestrating-Productive-Mathematics-Discussions/dp/0873536770, came first. I'm going to recommend my Woodrow Wilson advisor get these books as appropriate for next year's monthly seminars, since we're all math & science.) The first 2 chapters of this book really stressed that good discussions depend on the teacher's preparation -- choosing good things to discussion, moving the discussion along (with the talk moves), having questions prepared, & especially knowing where the lesson is going. A wandering discussion doesn't teach anyone anything, except that you can get off-track & never recover.
Our homework for our readings is to tweet about them. This proved to be somewhat dangerous, as Don retweeted what somebody said (it was about students showing what they know via whiteboards & the teacher being prepared with linking ideas & probing questions) & then a random modeler took issue with the statement, saying the students should ask the questions & link ideas. Well yes, that's the whole goal of modeling, but you have to be prepared to invisibly lead the discussions to where they need to go. This outside person didn't realize the original post was from a student in regards to a reading assignment. Anyways, the whole situation got a bit weird. Needless to say, "I strongly disagree" & "Mind your own business" have entered our group's in-jokes. :-)
Don also talked about stands-based grading some more (& in fact did a lunchtime Prezi on it a few days later). Here are the standards he uses for his Physics classes: http://gpschools.schoolwires.net/Page/12329 You'll note these aren't the state standards or the Next Gen standards -- Instead, he's combined them & condensed them down. (& in fact he's got performance standards too, like drop an egg off the building without breaking it, which aren't listed.) Students can see what exactly they need to work on instead of just "study harder". So I might try this in Physics next year, with a class of 15 rather than 25 or 30 (which I figure my other classes will be). The Physics kids are more likely to be willing to take a risk & the messing about with grades will be easier (Don averages stuff out with Excel first before he puts it in whatever online grade book). But I better see if my principal is on board with that first...
Equipment List
Shoot the Monkey Demonstration Kit, $68
http://www.flinnsci.com/store/Scripts/prodView.asp?idproduct=16289&noList=1
Long-range Projectile Launcher, $389
http://www.pasco.com/prodCatalog/ME/ME-6801_projectile-launcher-long-range/
No comments:
Post a Comment