Discussion Forum

 
  Forum  Discussions  Writing clicker...  problem-solving demonstrations
Previous Previous
 
Next Disabled
New Post 7/9/2009 2:17 PM
  kmellendorf
2 posts
No Ranking


problem-solving demonstrations 
Modified By kmellendorf  on 7/9/2009 4:17:36 PM)

I would like to use clickers to enhance demonstrations of solving problems.  When I do a problem at the front of the class, students often copy it down as a recipe to repeat for every problem in the chapter.  I want to use clickers to place the decisions regarding how to approach a sample problem in the hands of the students.  Just asking students for suggestions seldom produces any results beyond "I don't know."  Can I use clickers to make demonstrations of problems more interactive?

 
New Post 8/25/2009 11:51 AM
  pollock
4 posts
No Ranking


Re: problem-solving demonstrations 

 I have taught introductory physics with clickers many times, and do on occasion present clicker question sequences that "step through" what would formerly have been a traditional problem-solving example/demonstration on the board.

 

As a concrete example, there is a fairly canonical problem (solved in all texts in some form!), involving finding the electric field from a solid sphere of charge. It is a rather complicated problem, involving multiple steps that build on one another. For our purposes here, never mind the details -  what we did (and I stole this from Mike Dubson!) was to craft a sequence of clicker questions which involved what I considered the key steps in that derivation.  I asked the students to derive a formula for each sub-piece of the problem.  I "animated" the question slide so they first were asked to just do a little (one-step) derivation on their own, and only later (after giving them a few minutes to work on it) did I provide answers to click on (in the form of formulas, although one of was "something else")  This timing was an attempt to avoid them overtly "gaming" the system (I feared some students wouldn't work on it analytically, but just look at the multiple-choice answers and discard implausible answers) I was able to watch students - those who were not writing or gesturing or working were pretty apparent, so it was fairly easy even with 200+ students to get them all working on it.  The final clicker question in the sequence asked for a more general conclusion based on the work we had done, and was nice to consolidate the story and see if they were missing the forest for the trees. 

 

This worked out well - the derivation took considerably longer to get through, but the students had all worked on some of the steps. Even those who didn't get it correct had spent time thinking about what procedure they would need to use, and were thus primed for my explanations. What they did NOT get to do (which you might be after) was to decide at a higher level how to break up the problem in the first place, or which sub-part to tackle next, or why. This I facilitated through rhetorical questions, not clicker questions. So they were engaged in parts of the problem-solving story, but were "presented" with others. 

 

-Steven Pollock (CU Physics) 


Steven Pollock <> Physics Education Research Group <> University of Colorado, Boulder
 
New Post 9/2/2009 2:41 PM
  Margaret Asirvatham
4 posts
No Ranking


Re: problem-solving demonstrations 

 We have used clickers to engage students in quantitative problem-solving exercises in freshman general chemistry courses. Our approach is very similar to that shared by Professor Steve Pollock in physics. Calculation of the percent yield in a reaction containing a limiting reactant appears formidable to a novice. My colleague, Professor Veronica Bierbaum, designed a series of 5 questions to guide students through the process. In the first question, students were asked to write the balanced chemical equation for the reaction. Next, they calculated the number of moles of each of two reactants. Then, they determined the limiting reactant. Using this information, they calculated the theoretical yield of the product of interest. Given the experimental yield of the product, students could calculate the percent yield in the reaction. We encourage peer collaboration and have observed that students do not give up easily when working with a partner or a small group; besides, they can compare their answers. The series of questions are designed to convey the most important features in solving a multistep problem. Professor Pollock is right about the time intensive nature of these types of questions. However, they are extremely effective in addressing certain kinds of problems that many students find difficult or overwhelming.

 

Margaret R. Asirvatham

Department of Chemistry & Biochemistry

CU-Boulder, CO

 
Previous Previous
 
Next Disabled
  Forum  Discussions  Writing clicker...  problem-solving demonstrations