Serve as a Teaching Assistant¶

ECE 147C: Control Systems Design Project¶

ECE 147C is a lab-based class where junior- and senior-level engineering students apply the principles of System Identification and Control Theory to write a computer program to balance an inverted pendulum:

The cart and pendulum setup used in ECE 147C. (video)

For most students, ECE 147C offers their first chance to apply control theory to real hardware. This is exciting, but there are ample opportunities for frustration: faulty lab equipment; friction in the track; nonlinearities in the cart model; software bugs. Empathy — one of the themes in my teaching philosophy — was my key asset to aid the students’ learning in this environment. Often, the students’ code wouldn’t work and the pendulum would tip over and slam into the desk. Frustrated, the students would call for help, and I found that having an open, inquisitive, non-judgmental attitude helped set the stage for a fruitful debugging environment. It also helped that I had taken ECE 147C as a Mechanical Engineering undergraduate at UCSB in 2006, so I had suffered through the class and I knew how frustrating it could be.

ENGR 3: Introduction to Programming¶

ENGR 3 is an introductory programming course for Freshmen engineers. Using the Matlab programming environment, students learn the basic datatypes and control structures that underlie any program. About halfway through the course, students are introduced to more sophisticated mathematical objects like differential equations, and the students learn to solve them using built-in Matlab routines. Summer Sessions instructor Dr. Lina Kim taught ENGR 3, and I TA’d it with another TA, Michael Nip. Lina wrote the lectures and exams, and Mike and I wrote and graded the homework assignments, and ran the discussion sections.

One challenge with ENGR 3 was the students’ wide spread in programming experience. Some students were in the Freshman Summer Start Program (FSSP), meaning that they had started college a quarter early in order to get a jump-start on classes. Other students were retaking ENGR 3 because they failed it the first time. And still other students were not engineering students at all, but needed ENGR 3 to satisfy their department’s programming requirement. Moreover, some FSSP students took programming classes in high school, whereas others had never programmed at all. How can a teacher engage and guide students with such varied backgrounds? How should an instructor create different “learning pathways” for these different groups? As Jaime Escalante from “Stand and Deliver” says, “how can I reach these kids?”

Enrollment data for ENGR 3, Summer 2014. Students are spread across many years and many majors.

We approached this challenge in several ways. First, we let students choose which discussion sections to attend, regardless of which one they were enrolled in. Mike’s discussion section was more advanced and theoretical, and mine focused on emphasizing the core class concepts. This allowed experienced students to explore extensions to the material with Mike, while novice programmers could reinforce their understanding in my section. It turned out that most students opted to attend my discussion section.

Next, I learned my students’ names and asked them many questions. This kept my discussion section informal and increased participation, so I was able to ascertain my students’ well-being and focus the discussion where it was needed.

Also, Lina, Mike, and I used feedback cards judiciously throughout the course: Every Wednesday, Lina would distribute index cards and ask students to write what was going well and what needed improvement. We scheduled my office hours immediately after Lina’s lecture, so after class she would deliver the cards to me and I could react immediately to student concerns. Feedback cards provided a key mechanism to stay in touch with the students’ welfare and tune our office hours and discussion sections to suit the students’ needs. From a thematic standpoint, feedback cards helped me empathize with my students. For example, motivated by student feedback, I tweaked my discussion sections to involve problems more closely related to the homework. This was the first of many lessons in empathy: from the students’ perspective it’s natural that grades are the highest priority.

I took this feedback to heart. Instead of highlighting interesting applications in discussion section, I folded those applications into the homework assignments. The students seemed to enjoy them; one student even wrote a comment in his code thanking me for devising such fun homework problems!

I was interested to observe that different types of help and empathy were needed between ECE 147C and in ENGR 3. Seniors in ECE 147C were in the home stretch of their college careers and had somewhat “checked out”. They felt more aloof and would only ask for help as a last resort. I found it fruitful to have them explain their code to me as a peer, rather than have me dictate the correct code to them. For them, I played the role of a fellow engineer, helping them debug a common problem. On the other hand, my ENGR 3 students needed much more hand-holding. Taking their first tentative steps in college, they needed more guidance and reassurance. For the ENGR 3 students, I played the role of a mentor and guide.

ECE 147C¶

The ECE course evaluations are much shorter than the ENGR ones, so I received less feedback from ECE 147C. Five of my 11 students filled out ESCI evaluations for ECE 147C. This low turn-out was a bit disappointing but not unexpected since most of the class was seniors who were struggling to finish their senior projects at the time. My ESCI evaluations from ECE 147C were very positive:

Please rate your TA on the following scale.

In their open-ended feedback, the students considered me helpful and a fair grader, and they appreciated the extra lab time. Their ESCI open-ended feedback was sparse, but they posted two reviews on www.ratemyprofessor.com:

• Justin is a great TA! He was very enthusiastic about the class, and seems truly interested in the material. He gave me some really good explanations, that was helpful in understanding the material. I have no doubt that he will make a great teacher/employee in the future.
• Justin was very helpful and I think that he actually cared about helping us on the material. He is knowledgeable about the subject matter and very punctual and lab session in office hours. He consistently emailed us to keep us updated and gives us tips on the homework or lab reports. He is the ideal TA.

I felt encouraged by this feedback. It seems I was able to provide a good learning path for my students and empathize with their struggle.

ENGR 3¶

Twenty of the 24 students in my discussion section submitted ESCI reviews. For ENGR 3, the ESCI reviews contained 20 questions and an open-ended response question. Histograms of my performance appear in Appendix 4. From these data I observe:

What’s going well

• The students found me enthusiastic, clear, knowledgeable, and approachable.
• They liked my lecture slides.

What needs improvement

• Some students felt I moved too fast, while others felt I was a bit repetitive. This could be due to the large spread in abilities in ENGR 3, but it’s certainly possible I sped through some parts and harped on others. I probably should have asked for more in-class feedback of the form “thumbs up if you’d like me to go faster, down if you want slower.” I employed this technique frequently a year later, when I taught ENGR 3 as Instructor of Record.
• Some students felt that discussion section only contributed moderately to the course. I imagine that those students wished my discussion sections had been more directly applicable to the homework; I took care to not give homework answers in section, opting instead for developing the week’s concepts with my own examples. In hindsight, I realize that students care primarily about their grades, so if a discussion section doesn’t clearly relate to improving their grade, they may tune out. In the future, I will try to find a suitable balance between giving away answers and holding their attention.
• Some students felt I only somewhat conveyed the usefulness of the subject matter. In an introductory class, it is sometimes difficult to motivate the very basic material with cool examples. But it is important to try to make the material as interesting as possible. After all, one of my teaching themes is: The instructor must provide a purpose and a path. So I will try to find more stimulating examples. (Note: A year later, when I taught ENGR 3 as instructor of record, this backfired because I made the homework problems too stimulating (too hard)! So there is a balance.)

There were five open-ended responses in the ESCI surveys:

• Best TA I ever had. Very helpful and makes you want to learn the material. Hire him as a professor.
• Justin is a great TA. Very easy to talk to you. Very friendly and enthusiastic.
• Enthusiastic and really helpful. Thoroughly explains material when asked.
• Sometimes he takes a while to explain something but I always understand by the end which is more important so I didn’t bother me too terribly.
• Amazing TA. Always make sure his students understand the material. Also learned everybody’s names.

I appreciate this feedback. It identified ways I can be more empathetic — e.g., by focusing my teaching on what the students care about — and indicated that I succeeded in my efforts to connect with the students — e.g., by learning their names and offering friendly explanations.