Buy that special someone an AP Physics prep book: 5 Steps to a 5: AP Physics 1

Visit Burrito Girl's handmade ceramics shop, The Muddy Rabbit: Yarn bowls, tea sets, dinner ware...

04 March 2013

Hint for improving presentations: strict time limit, no powerpoint

I don't know how many of you have students present their work to the class.  I know I didn't for many years, because I was so scarred by my own high school experience watching "um, well, we, um, took lots of data and averaged it and got the results you see here, which blah blah blah ad infinitum."  When I began teaching research, I didn't have a choice about teaching presentation skills, as the scientific talk is the typical and obvious method for disseminating research results.  

Certainly I had considerable success by insisting on repeated practice -- the more times someone gives the same presentation, the better that presentation gets.  I required practice in front of me, in front of other science teachers, in front of peers, sometimes even in front of a video camera.  Nevertheless, I would still get a non-negligible number of practically unwatchable presentations, the kind that I'd be embarrassed about if a colleague happened to be around.

The best tip for improving student presentations came from my colleague Ray Smith during debate practice.  I may be (for now) coaching the debate team, but Ray is a real debate coach.  He knows all sorts of little tricks for helping students write and deliver their speeches.  

One of our younger debators had written an excellent case, but was tripping over words, struggling to read it smoothly and within the six-minute allotted time.  Ray took his printed speech away from this gentleman, and told him, "You know this case.  Give me the speech right now as best you can from memory, no reading, no notes.  Just relax and take six minutes to explain your case to me."  

And wow... the student did a great job.  He took a giant step that afternoon, recognizing viscerally that the printed speech is not supposed to dictate the words to be delivered, but rather should serve as a guide and reminder for him to communicate the essence of his case to an audience.

We used this idea a couple of years ago when we needed to select one of three students for our USIYPT team.  They all had struggled to some extent giving a powerpoint presentation.  

So we took the powerpoint away!  

We gave them three days to prepare to give a 5-minute talk with only whiteboard and marker, with no other props.  The presentations were all improved, but one stood out clearly to everyone present -- he made the team.  

This year, we have a group of seven students doing biomechanical research into sprinters' "block starts".  In the fall, they gave a group talk with powerpoint, in which they took 45 minutes to present their results. While the results were in fact excellent, the manner in which these results were presented was abominable to this debate coach.  Some students know what they were talking about; others rambled for five minutes discussing each of 30 data points on a graph.  The poor presentation distracted from the beauty and strength of the outstanding physics they had in fact done.  

This trimester, their research supervisor was concerned that not everyone was pulling appropriate weight -- he thought that a similar group talk this time would put an unfair burden on the two or so students who had done the majority of work.  So we did the 5-minute, whiteboard-only thing again.  But this time the presentation was to be given not to the research supervisor who had been in charge of the project all year, but to a teacher who was utterly unfamiliar with their work.*  

*That'd be me.  It did help that these students, who don't know me well, were slightly intimidated knowing that I would be judging their exam.  They prepared better given that unintentional intimidation.

In research especially, new eyes are critical.  Because they had not ever worked directly with me on their projects, the students had to consider their audience.  We discussed in advance how I know physics well -- they don't have to explain what impulse is -- but since I haven't been working with them, they DO have to explain what they've measured, how they've measured it, and what it means.  In some cases, this meant that students had to figure out for themselves what they were doing and why.

The strict 5-minute time limit worked wonders, too.  The students had to make carefully considered decisions about what was important and what wasn't; they had to practice their talk well, because they knew that I would have no guilt in cutting them off at the 5-minute time limit.  In the event, I saw seven generally well-explained summaries of two month's worth of research.  

What's best is that through these seven presentations I learned a bunch about the physics behind the sprinter's block start.  Apparently there's a tradeoff between standing high and standing low in the blocks -- a "low start" provides more impulse and thus more initial speed out of the blocks, but keeps the runner on the blocks for about an extra tenth of a second.  The "high start" provides a lower initial speed (by a few tenths of a m/s), but gets the runner off the blocks quicker.  I'm now quite interested to see how these folks investigate how this tradeoff resolves itself over a longer portion of the race.




2 comments: