Robert W. Arts, Ph.D. Professor of Education & Physics University of Pikeville Pikeville, KY Presented at the Spring Meeting of the Kentucky Association of Physics Teachers Bowling Green, KY, March 17, 2012

 “…basically an experiment where physics students attempt to obtain a specific outcome under some sort of constraint conditions set by the instructor. The students must work within the constraints set by the instructor and they must work only with the equipment given by the instructor" (Jones, TPT, 2009).

 I have been very dissatisfied with many of the traditional cookbook laboratories offered in physics. Additionally, I have experimented with a number of alternative laboratory practices such as inquiry based, activity-based, and project-based; none of which I really felt connected with. As such, I have taken to incorporate a number of "challenge" laboratory activities in each semester of my general physics courses for science majors.  Additionally, we have recently added the requirement of General Physics I & II to the middle grades science education major. Their ability to use applied knowledge and to think ‘outside the box’ is paramount to their success in science courses.

 In general, all challenge labs are graded in two parts  The Theory: The laboratory notes taken during the challenge outlining the method/course of action taken. This includes, but is not limited to, a procedure, a correctly illustrated free-body diagram and a list/explanation of the equations used.  The Experiment: Actual experimental results (numerical value, wiring diagram, etc.).  Each group submits a final report and as such each member receives the same grade for the work

 Challenge lab instructions are designed to be clear and simple. As a result, students clearly understand what they need to accomplish and set out immediately trying to solve the problem.  Challenge labs force students to deal with many of their misconceptions in a fun and interesting way.  If their physics is wrong, they get instant feedback from their experimental trials. You can allow a group to make a second attempt for a reduced grade, if applicable.  Student motivation to do well on these challenges is always high. This generates a great deal of vigorous discussion and various attempts to solve the problem on paper prior to attempting an experimental run.  The students converge on correct answers as they discuss their ideas and usually the good physics wins. When any group is ready for an experimental attempt, every other group stops to watch the action. The lab generally fills with cheering students when a groups experimental trial goes well!  There is something about this competition aspect of these challenge labs that students really seem to like.

 It has not been possible to compare previous year’s lab grades to labs which have incorporated these challenges  Apples to Oranges  However, comparative results of quiz and exam scores for these two groups seem to suggest that those students exposed to the challenge labs have a greater degree of higher order thinking and as a result a higher score on these assessments.  Time will tell as more data is collected

 “They were stressful at the time but after the fact I knew I knew what I was talking about and felt more confident from it.”  “At the time I did not like the challenges. Now, having finished the course, I see the value in what we did in terms of my ability to apply what I have learned as opposed to simple regurgitating memorized information.”

 The purpose of this challenge laboratory is to match a series of motion graphs. The challenge is designed to further an understanding of how to construct and interpret graphs of position or velocity versus time.

Comparative integration yields approximately a 1% difference Comparative integration yields approximately a 6% difference

 The inclination angle of the track (  ), the mass of the cart (M C ), and the distance (d) between the photogates are all fixed—they have been and cannot be changed. Groups draw both a station number and target time. The challenge is to determine, theoretically, the hanging mass (M) required to produce the target time and to experimentally verify that prediction. The challenge is fairly open ended and each group is free to attack the problem any way that they see fit.

 Provided is a configuration of six light bulbs (one 15W, two 40W, two 75W, and one 100W). The bulbs are arranged at the points of a six-pointed star on the top of the box. The triangles of the star points are color coded (Red, Orange, Yellow, Green, Blue, and Violet) to assist in describing the system. Each lamp socket is also equipped with its own on-off switch.  The Task: To identify how the six light bulbs are connected together (without opening the box.).

 Challenge labs and other experiences like it are an invaluable part of learning physics.  The experience teaches physics students how to solve problems and to apply physics to laboratory phenomena.  Many common laboratory experiments and physics problems can be turned into challenge labs.  I currently have 8 challenge labs each year (1/3 of the total labs completed) that are interwoven with traditional laboratories.  The teaching advantages to using lab challenges are numerous:  Motivation for students  Creates authentic learning experiences  No complex lab handouts for students to read; yet students must use applied knowledge from lecture and pervious laboratory experiences in order to solve the challenge  Easy grading  No laboratory report to complete at home