S.G. Alexander, Associate Professor of Physics

The recent article in the Miami Student titled “ ’Scaling Up’ the dropout rate for Physics department” by Alyssa Melendez asks the question “are Miami Physics professors intentionally making their classes unreasonably hard? Are they trying to weed people out?”

Ah, the weed out course; this myth has been around for at least forty years, and probably a lot longer.  In fact, I remember invoking it myself during my first year of engineering school at Penn State back in the mid 1970’s. During term break, I remember my mother calling from the kitchen, “Stephen, would come in here for a minute.” I knew that when she called me Stephen that she was likely upset. When I arrived, she was holding my grade report from the just finished term (in those days, parents received your grades in the actual mail).  I already had a good idea what she was looking at: a B, a couple of C’s, and, yes, one even worse than that. She looked at me over the tops of her glasses and said, “what’s going on here? You were an honors student in high school and never brought home grades like this.”  I tried to explain to her that the courses I was taking, Calculus, Chemistry, and Physics, were very difficult, and, echoing what I heard from other students, that these were well-known “weed out” courses that are unreasonably hard and intentionally designed to limit the numbers of engineering and science majors. My mother didn’t respond right away, but she took off her glasses and looked right at me and said, “oh, I was not aware of that, but, if that is indeed the case, I suggest that you work quite a bit harder so that you don’t weed yourself out.”

Eventually I did take my mother’s advice, and I finally realized that increasing the level of my effort was the only way that I could succeed as an engineering major.   I was able to graduate on time with a respectable, yet quite unspectacular, GPA just above a 3.0.  I applied for five entry level engineering jobs and received five very good offers. It was during the interviews for these jobs that I finally learned why the courses that we took were so damn difficult, i.e. “weed out classes.” More than one interviewer commented how much they liked to hire engineers from Penn State. The rigor of the program guaranteed that anyone who completed it really has acquired the necessary knowledge and skills to be a successful engineer that a company would be eager to hire. In short, the value of my recently acquired diploma was determined by the reputation of the quality of the program. A few years later, when I applied to Ph.D. programs in physics, I relearned this lesson. I applied to six programs and received six offers of admission, all with assistantships or fellowships.

At Miami, are the introductory courses that engineering and science majors take more difficult than high school courses or courses at some other college or university? Yes, they most definitely are. Do all of the students who come to Miami to major in engineering or science pass these courses? No they don’t. Why is that? The rigor of the program determines the value of the degree. Our goal is that when you leave Miami with your degree in hand that it will have a high value in the marketplace of jobs and/or graduate/professional school admissions.

Several points in the article require clarification or correction. The description of the SCALEUP format adopted here at Miami is not adequately described.

Prior to two years ago, all introductory physics classes were taught in a lecture format where students listened and took notes as the instructor covered the material and did example problems. The most frequent student comment that the department received during this time was, “I understand everything that you do in lecture, but when I try to do the homework problems, I don’t know where to start.”  This represented a real problem for both the instructors and students; exams consist entirely of problem solving – if students don’t know where to begin their homework problems, they surely will struggle with exams.

The Miami version of SCALEUP is based on the two premises:

(1) learning physics is hard for most students, and

(2) most students learn best by active participation in hands-on activities, especially problem solving. Our approach to SCALEUP is divided into three activities:

Reading Assignments. Students are assigned to read a few sections from their textbook before class. We realize that most students won’t completely understand what they have read – it is the rare student or professor for that matter, who can understand a new topic in science or engineering with the first reading. But, it is the necessary starting point.

In Class Work. The instructor briefly lectures on the most important topics from the assigned reading, concentrating on those ideas that are essential for applying the material to problems. Students then work in groups of three to solve problems on whiteboards or do lab activities.  The purpose of this is to address the student comment “I understand everything that you do in lecture, but when I try to do the homework problems, I don’t know where to start.” We bring this step into the classroom where students who are confused can get help from their classmates, teaching assistants, and the instructor. This pattern of short lectures followed by a student activity is repeated for the entire class. All of us have noticed that students are typically baffled with the first few whiteboard problems, but as the class goes on, most are showing definite signs of beginning to understand the material.

Homework. Several problems covering the material from class and similar to the whiteboard problems are assigned for homework. Students may work on these independently or in groups. If they need it, students can get assistance on their homework from each other through an online student discussion site (Piazza.com) that we have set up. In addition, our graduate teaching assistants staff a drop in help center where students can ask homework questions, and all of the instructors have office hours.

Does the Miami version of SCALEUP work better than our old lecture based format? That is a difficult question to answer. It would be nice if we had a set of students who could take the entire course in the lecture format. Then, we could wipe their minds clean, and have them repeat the course under the SCALEUP format and see if they do better. To date, we have had no volunteers to participate in this study. Most instructors agree that in a subject like physics, there are about ten percent of students who will excel and get A’s no matter what you do and about ten percent who will fail or withdraw no matter what you do. Jennifer Blue who does research in physics education is trying to determine if we are making a positive impact on those in between students who, with SCALEUP,  may get B’s instead of C’s or C’s instead of D’s. Is SCALEUP a Harry Potter-like magic wand that can be used to wave over students’ heads and they will magically become educated in physics? No. Physics has always been and always will be very difficult to learn. There are no magic wands, only hard work. Our hope is that SCALEUP is a better way to attack the hard work part.

Final Grades in PHY191. The article states that for PHY191, “the class average is an F, over 10 percent of the students have dropped.” The data provided on the Miami registrar’s website shows this final grade distribution for PHY191 for fall semester 2016: 17% A, 31.5% B, 20.5% C, 8.5% D, 7.9% F, 14.5% W with a course wide GPA of 2.48 which is in the C+/B- range.  It should be noted that the Miami Bulletin defines a grade of C as “Satisfactory,” which we interpret as meaning that the student is adequately prepared to take any course having PHY191 as a prerequisite. While we don’t like the DFW numbers in the distribution, they are very typical of the other first year courses taken by engineering and science students at Miami, see e.g. CHM141 and MTH151.

Exam Format.  In a perfect world, every physics class would have no more than about 30 students, and the instructor could give exams where students are required to solve problems and show all of their work, i.e. free response problems. In this perfect world, the instructor should be able to see the process by which the students arrived at each answer.  In the real world of PHY191, we have almost 500 students for three instructors. We would like to live in that perfect world, but we don’t. Over the years, we have experimented with many different exam formats: all multiple choice, multiple choice with partial credit, and a combination of multiple choice and free response. Last fall, we got permission from our chair to use graduate teaching assistants to grade free response problems for exams, so this year we are giving exams that are 70 percent multiple choice and 30 percent free response. Many students are of the opinion that multiple choice questions trip them up: “I was frustrated with the multiple-choice exams, and that was the main thing that messed me up in the end. Like, I understood the concepts, but I would make a tiny mistake in the problem, and it would cost me five percent.” This may be true in a few problems for a few students; however the bulk data shows that in every exam that has a multiple-choice and a free-response part, the average for the free-response part is always close to or usually less than that for the multiple-choice part.

In addition, Jennifer Blue is misquoted in the article as saying: “exam scores became so bad after the switch to SCALEUP, that professors had no choice but to drop the students’ lowest exam score.” This is not true. Exam scores are roughly the same as they were before switching to SCALEUP. The decision to drop the lowest exam score for each student was made for two reasons. For every exam, there are several students who have to miss the exam due to illness or other personal reasons. Instead of giving many makeup exams, it is much cleaner if the missed exam becomes the one that the student drops. Students who miss an exam are still responsible for the material as the final exam is comprehensive, i.e. covers the entire course, and every student must take the final exam to pass the course. The second reason from dropping the lowest exam score is that students have requested such a policy for years. Many students say that they should not be penalized for having one bad day; we agreed.

So, in the final analysis, is the physics department at Miami trying to weed out students from majoring in engineering or science by making our introductory courses unnecessarily difficult? No, our goal is to have courses that have as much rigor as possible so that students are prepared for their upper-level courses and ultimately leave Miami with a degree that has the highest possible value.

Comments