Archive for the ‘College’ Category

My Design for Organic Exams

Tuesday, October 21st, 2014

ed_academic_bigIt’s fall semester at SLU, and I’m teaching organic chemistry for our majors once again. Last year, I was focused on just getting through the course. I was so consumed by producing slides, homework assignments, practice exams, and real exams on a tight schedule that I didn’t get to think hard about the finer points of design until the class was over. Now, on the second pass, I can focus on making improvements rather than creating everything from scratch.

At SLU, instructors don’t get assigned TAs for proctoring and grading unless the class has greater than 30 students. In the spring, the majors’ class fell below this number and I had to think about designing exams to make grading as efficient as possible without eroding their effectiveness as tools for teaching and thoughtful evaluation. The system I settled on was different from my experience in both college and grad school, so I thought I’d share.

I’ve settled into a system in which quizzes and exams generally have four or five sections/problems picked from the following varieties: multiple choice, mechanism, synthesis, A+B reactions, explanations, and calculations. While I’ve never been a huge fan of multiple choice, it allows me to test a variety of straightforward points without the strain of having to grade a wide assortment of free-response questions. My multiple-choice questions are typically five choices, with students getting +5 points for a correct response and +2 points for leaving a question intentionally blank. This scoring system introduces a penalty for guessing; students need to recognize that sometimes the best option in life is to admit “I don’t know.”

In my system, if there is an exam on Wednesday, the students have a quiz due on the previous Friday that covers the same material. Each quiz contributes 2% to the final grade in the course, while each exam contributes 20%. The quiz has the same length, format, and answer sheet as the exam, except the problems are harder to compensate for the fact that I give students 48 hours for the quiz and allow them to talk with each other about the answers. I like how this approach requires the class to be familiar with the exam material almost a full week before the exam, and that students have an incentive to form study groups and debate answers to hard problems. I never learned as much in organic chemistry as when I was trying to defend my proposed answers to classmates. Finally, having what is essentially a hard practice exam due on the Friday before the “real” exam means that I can return it graded and marked with comments by Monday. In many cases, these quizzes serve as wake-up calls to students while there is still time to fix issues that need attention.

In every chemistry class I’ve taken, students either wrote their exam answers directly on the problem booklet or in small blue exam books. I find these response media are murder to grade because you spend so much time flipping through pages, hunting for answers, and flipping back to write the subtotal for that problem on the cover page. And, of course, there are always two or three students who get creative and write their answers out of order or on the back side of pages.

To solve this problem, I started writing exams such that students have to place all of their answers on a single letter-sized piece of paper. I draft an answer sheet for each exam on which it is clear where each answer should be written. When the answer is a single word or structure, I’ll typically draw a box for it. The use of a single sheet minimizes the burden of flipping, while the answer boxes (located at the same spot for every student) minimize the burden of hunting. Here’s a sample answer sheet typical of one of my orgo exams:

sample_exam_answer_sheet

I copy answer sheets onto 65-lb. card stock so that both sides of the sheet can be used without the pen ink bleeding through to the other side. I find that the smooth sheets sold under the Neenah brand are better than sheets of the less expensive Staples brand, which have an annoying coarse texture on one side. The card stock also gives a regal quality to the answer sheets. These puppies are suitable for framing and will withstand decades of wear if pinned to the refrigerator door of a proud parent.

Another nice thing about having students limit their answers to a single sheet is that the entire stack for the class can be scanned without hassle. Most modern office copiers are capable of sheet-feed scanning, so if your exams have no staples, you can scan the entire stack of paper all at once and e-mail the data to yourself as a single PDF. What a wonderful miracle of technology.

I scan the entire set of answer sheets both before and after I’ve graded them. In doing so, I have a permanent record of performance that I can access for eternity. If there is an issue over improper grading or a student attempting to cheat by altering answers upon return of the graded copy, I can refer to the electronic file. If a student needs a letter of recommendation two years down the road, I can open up the file and make specific comments about his/her performance. And if I want to mine data in the future for some pedagogical purpose or project, all of the data will be available for analysis.

A final important feature of each answer sheet is that I have a line for students to write their names at the top of the back side. This makes returning exams very simple, because I can fan them in columns in alphabetical order on a table and have students come in groups to pick them up. With only the top inch of the back page of each sheet exposed, students cannot see each other’s grades. Of course, as the columns thin out, I adjust the sheets to prevent greater exposure.

As I discussed before, I allow students to bring handwritten notes into exams. They serve to emphasize that organic chemistry is about analysis—not memorization. Also, having students organize the information of each unit onto a single sheet of paper forces them to make connections about the material in their minds ahead of the exam. This semester, I’ve started collecting, scanning, and returning these note sheets as well. I am fascinated at how students organize their thoughts, and I plan to use this information in my future letters of recommendation when appropriate. How an individual organizes her thoughts on paper gives you an interesting window into her mind.

So, that’s the system. Are there drawbacks? Yes. I tend not to write long mechanisms or synthesis problems that go over four steps, because there isn’t enough space to do so. With that said, I’m not sure if these problems offer much added benefit relative to alternatives with more concise answers.

One thing that I’ve found surprising is that even though the answers for the exam all fit on one page, there are students who still feel they need three hours to finish. I thought that offering four shorter exams instead of three longer ones would make time a non-factor, but often at the end of two hours, I still find myself nagging for all of the papers to be turned in.

Anyway, I like how this system works and will continue to modify it to work better for both the students and me. It is ironic that as a teacher, I feel that I am the one in the classroom who has the most to learn.

UCLA Professor Patrick Harran Strikes Deal with Prosecutors

Sunday, June 22nd, 2014

BulldoodyPatrick Harran, the UCLA professor who faced four felony counts in connection with the death of Sheri Sangji in a laboratory fire, has struck a deal with prosecutors that allows him to avoid charges in exchange for a $10,000 fine, 800 hours of community service, and running a lab free of safety violations. So long as Harran completes his end of the terms of the agreement, he will avoid trial and have an untarnished criminal record.

What a relief!

As an assistant professor in charge of a research lab, I could not be happier with this outcome. I have a lot of stuff to worry about, and ensuring the safety of my students cannot be allowed to get in the way of important things like finding consulting gigs, collecting awards, traveling to international conferences, and stealing ideas for grants. All of those OSHA rules are meant for industry, not academia. The bar for what passes as safe in academic labs is clear, and people who want to work under moderately safe conditions know better than to go to graduate school. The government simply can’t expect me to be responsible for what happens in my lab, which is well over 50 feet from my office and not even the same direction as the restroom. I’m happy to buy enough safety goggles and almost enough lab coats to outfit my students, but the rest is up to them. If Aldrich has written a technical note on their hazardous experiment, my students know not to bother me.

The most important aspect of the Harran deal is how it extends the long, proud tradition of excusing PIs of any professional responsibility for their work. Society recognizes that professors are only supposed to have good things happen to them. We get the lion’s share of credit for papers, not the students or postdocs. We get the big salaries, not the students or postdocs. We get the awards, not the students or postdocs. On the flip side, professors must be protected from negative consequences at all costs. If an accident happens in one of our labs, that’s the students’ fault. If multiple papers from one of our labs contain fabricated data, that’s the students’ fault as well. Clearly, professors are not responsible for supervising their groups for integrity or safety. We know this because Dalibor Sames and Patrick Harran are still in charge of their labs. I applaud Columbia and UCLA for recognizing that you can’t discriminate against professors for trivial things like irresponsibility and incompetence. Anyway, it’s the competent professors you need to watch—lightning never strikes twice, right?

Of course, I realize that there should be some consequences when something truly horrible happens. In these situations, professors must arrange for perfunctory punishments that allow all of the parties charged with oversight to save face. That’s what we saw here: UCLA threw some money at a scholarship in the victim’s name and at establishing a safety program it should have had in the first place. Personally, Harran was forced to donate money to the hospital where his student died. Incidentally, I think $10,000 was way too much; the man only earns $301,000 a year. How is he going to make ends meet with just $291,000? At least Harran’s lawyers were clever in how they disguised the 800 hours of community service as a major inconvenience instead of court-mandated preparation for the Broader Impacts section of Harran’s next NSF proposal. Killing two birds with one stone is exactly why good lawyers get paid the big bucks.

In all seriousness, I think the deal agreed to by prosecutors is a grave injustice, but one that comes as no surprise in today’s legal system. Without any changes to the material facts of the case, how does the DA go from charging someone with four felony counts to striking a deal that allows Harran to have a spotless record with a payment, community service, and actually doing his job of running a lab free of safety violations? Note that this was not a plea bargain; Harran pleaded guilty to nothing—not a misdemeanor, or even an infraction.

The game plan of Harran’s legal defense was quite effective: delay, delay, and delay. They gummed up the works with continuance after continuance and motion after motion. In the end, it appeared the prosecutors were willing to do anything just to clear the case. I mean, was this deal what the prosecutors were holding out for all of these years? What makes it all the more worse is that the original deal called for 400 rather than 800 hours of community service. The judge had to step in and double it.

My heart goes out to Sheri’s family for their loss. While I think our legal system has denied them justice, my hope is that the field of chemistry does not forget what happened to her. I hope UCLA’s reported new-and-improved safety culture persists, and I hope the rest of the world of academic chemistry also strives to do a much better job regarding safety than it has in the past. At the very least, I can guarantee you that Sheri’s death has had an indelible, positive effect my approach to safety and how I manage my lab and students.

 

For more coverage: C&EN’s Jyllian Kemsley and Michael Torrice have done a fantastic service for the community in covering the case, and Chemjobber has been curating links to coverage on his site.

How to Use an iPad for Orgo Lectures…and Embarrass Yourself

Wednesday, June 18th, 2014

I am not a fan of chalkboards. Chalk is messy and always ends up somewhere on my clothes by the end of class. I also regularly encounter chalkboards that don’t erase well and become unreadable as more and more dust gets smeared across the slate. When I was in grad school, Andy Myers solved this problem by having his teaching assistants clean the board with water and squeegees *during* class. While I am not afforded the benefit of a squeegee team at SLU, I suppose we could hire some adjuncts.

Though I am not a fan of chalkboards, I am a big proponent of drawing structures and working problems during class. In the fall, there were a couple of times I resorted to using transparency film and colored pens. It worked, but it was clunky. In an effort to step up my game, over winter break, I went on eBay and shelled out some cash so that I could ditch the transparencies and use my iPad instead. My tool kit now includes:

1 iPad
1 tablet stylus
1 Apple lightning-to-VGA adapter
1 VGA switch box
2 VGA cables, 6′ long
1 handsome bag for transporting everything in style

ipad_teaching_kit

Prior to class, it usually takes me three or four minutes to turn on the projector, load my PowerPoint slide deck on the room computer, and plug my iPad into the projection system. This involves connecting the iPad to the projector through the lightning-to-VGA adapter and a VGA cable. If the room only has one input servicing the projector, you’ll need to use the VGA switch and a second VGA cable so you can toggle between your slides and the tablet.

Writing with the device is pretty simple. I use the app called Notability, which costs $4.99 and is worth every penny. Before class, I’ll upload PDF files of any quizzes or exams I want to review that day onto Google Drive, then download them into Notability on the tablet. Once you’ve done this, you can write/draw on top of the document and screencast everything through the projector. Here’s a screenshot of a typical session:

notability_example

I love the number of colors to choose from and the fact that you can save the marked PDF and post it for the benefit of the class. I’m still getting the hang of drawing structures as crisply as I would like, and I think part of the problem is the thickness of my stylus. I’m also considering buying a tablet with a wider screen, because things can get kind of cramped on the iPad.

While the overall system was recognized as an improvement by the students in their course evaluations, I should mention one little slip up I had in class. On average, I used the iPad for 5–10 minutes per lecture, and the vast majority of that time, I wasn’t connected to the Internet. On March 7th (the first Friday of Lent), I forgot to load the quiz/exam onto my iPad ahead of time. But the fix was simple: I could just connect to the Internet, download the file off the cloud, and be good to go.

So, that’s exactly what I did. What I forgot to do was to shut off the wireless connection after downloading the document. As I was going over the solution to a problem, the familiar chime of a Facebook message erupted from my iPad along with the following notification:

tarapushalert

The full message (which is truncated in the push alert) was:

tarachadconvo

Funny stuff. One of the many reasons I love my wife is her fantastic sense of humor. But at the time, all I remember seeing was “no meat” as I desperately tried to make the notification go away. The class was laughing pretty hard, but I wasn’t sure if it was at the content of the message or just the fact that a message had unexpectedly interrupted class. My worst fears were confirmed later in the day, when I had Tara re-send the message so I could see exactly how much of it showed up on the screen. I was hoping the worst of it was truncated away. Unfortunately, the worst of it was not.

I was pretty mortified, but I got over it. My main sources of solace were that (i) the students were a pretty cool group, (ii) the statement was a joke, and (iii) it could’ve been much worse considering other subjects Tara and I have discussed by text message.

At least my students were entertained by the exchange. I was able to find the Twitter accounts of a few of them by searching for my name, and sure enough, the incident made their feeds:

twitter_conversation_orgo_censored

Anyway, the take-home message is to put your iPad in “airplane mode” or turn off push alerts (and texts) to avoid disruptions and potential embarrassment during class. Or you can just marry a prude.

Some lessons are learned the hard way.

The Pauper Professor’s Orgo Library

Wednesday, December 11th, 2013

chembarkfc_kit_200Well, it looks like I’ve been ignoring the blog again. Sorry about that.

We are in finals week here at SLU, and the end-of-the-semester crunch has definitely crunched me (with a lot of help from lab stuff, two chemistry “business” trips within the last month, and the fact that I will be getting married in two weeks (!).

I’m teaching Organic 1 this semester, and it has consumed an inordinate amount of time. But the experience has also been a lot of fun and a good training ground for figuring out how to run a class efficiently.

Like many orgo teachers, I began the year by insisting to the students that the best way to do well in the class is to work practice problems (and lots of them). When I was a wee lad taking orgo at NYU, I walked uptown to the fantastic Barnes & Noble at 5th and 18th and bought copies of Vollhardt and Streitwieser to supplement the problems in Jones. My weekly routine was to read through the Jones chapter in two nights while also making index cards that cataloged each reaction along the way. The rest of my week would be spent doing all the problems in Jones, then as many in Streitwieser and Vollhardt as I could stomach.

But textbooks aren’t cheap, and I feel icky about asking students to shell out extra money for supplemental problems after they’ve already forked over $260 (!) for the class’s required textbook. Of course, the used-book market is flooded with cheap, old editions of organic textbooks.

Over the course of this semester, I undertook a mini-project that involved scouring half.com for deals and assembling a small library of textbooks and solutions manuals as a resource for my sophomore organic students. The last volume arrived two weeks ago, and now my collection occupies almost an entire bookshelf in my office:

cheap_orgo_textbook_library

There are 16 books there: 8 sets of texts and solutions manuals. Here’s what I paid for each book + manual:

Bruice: $3.43 + $0.75
Carey: $3.26 + $0.75
Heathcock/Kosower/Streitwieser: $1.05 + $1.18
Jones: $0.75 + $0.75
Loudon: $4.07 +$4.12
Smith: $0.00 + $0.00 (this is the one SLU uses)
Vollhardt/Schore: $1.05 + $0.75
Wade: $2.22 + $0.75

Those costs are steals compared to the prices listed on Amazon. The shipping on each item ranged from $1.89 to $3.99 and was always more than the cost of each book. In total, my little collection set me back $74.14. The plan for next semester is to cart them over to the main library where they can be kept on short-circulation reserve. Students can check out the books for a day at a time—long enough to work or copy the problems in a chapter, but not long enough to hog the resource. Anyway, with eight texts as options, I’m hoping the market for orgo practice problems at SLU is now saturated. I should never again hear wailing about there not being enough practice problems available.

Anyway, the final exam for my class is this Friday—the 13th. I expect the only students who will encounter bad luck are those who haven’t been working enough practice problems.

Organic Chemistry Exam Show-and-Tell

Wednesday, November 13th, 2013

ChemBark's Orgo BunnyWhen I was in college, there was a professor who was notorious among the grad students for stopping them to show off his organic chemistry exam questions. Unlucky TAs on their way to the bog would get tied up for what seemed like hours going through drafts of exams in the hallway.

But now I think I know how he felt. There’s a certain degree of satisfaction associated with writing a problem that makes students integrate their knowledge of multiple subjects within a given set of consecutive chapters in whatever textbook you’re using.

Instead of stopping TAs in the hallway at work, I figured I could move the practice into the 21st century by using the blog. I’ll post any gems I’m proud of in this thread. Feel free to share your favorites as well.

To start…

Exam 1, Problem 3-2. (8 points) Draw the most (Brønsted–Lowry) acidic, optically-active isomer of C6H10.

Click here for the answer. The chapters for this exam included acids and bases, isomerism, functional groups, alkanes, and stereochemistry.

Doctor? No.

Wednesday, October 16th, 2013

bracher_office_doorI generally like to be respectful of people. Toward this end, I try my best to address people properly. You’ll find that I’m pretty liberal in using “Dr.” when addressing letters and e-mails, because you never know when someone is going to get upset at being called “Mister”. In contrast, few people seem to get upset at being called a doctor when they are not. When I was applying for faculty positions last year, I am certain I conferred Ph.D. degrees on a multitude of unsuspecting departmental staffers whose job it was to assemble the applicants’ files.

On the flip side, I have a personal aversion to signing anything as “Dr.” I always check “Mr.” when filling out forms, and I cannot bear to end an e-mail with “Dr. Bracher.” As I am now a teacher, this has established a weird dynamic where students address their e-mails to “Dr. Bracher” and I return them by signing “Paul.” I know this has got to weird the students out because I remember fretting over how to address professors when I was in college. Do you call them “Professor”, “Doctor”, or by their first name? I am pretty sure I always opted for “Professor.”

In my undergrad research lab, it was always a big deal for students when the boss started signing his e-mails to you by his first name. It was an unmistakable signal that you had made it and was regarded as a rite of passage in the lab. In contrast, my graduate and postdoc advisors were pretty much known exclusively in the lab by their first names. Of course, the undergrad-professor dynamic is much different from the dynamic with grad students and postdocs, but it’s always interesting to see how these differences manifest themselves.

Some students attempt to solve the e-mail problem by using the non-direct “Hi,” “Hey,” or “Hello there” salutation. Of course, in trying to avoid any awkwardness, this device mostly just draws attention to it. Would you walk up to a professor and address her as “Hey”? Some of my colleagues sign their e-mails to students as “Dr. D” (or similar), which is an interesting compromise between formal and informal. At the same time, it makes me question what I should address these professors when we are in front of students. Can I say “John” (as I normally would), or should I say “Dr. Doe”?

While I don’t especially care what people call me and would never be offended by any of the standard choices, I prefer “Paul”. But after two months in St. Louis, it seems as if I’m going to be “Dr. Bracher” to the vast majority of students. To friends, colleagues, and those online, I will still be “Paul”, while to family at home, I have always been “P.J.” All are fine with me.

Yesterday, I found myself reconsidering whether to sign my e-mails to students as “Dr. Bracher” to make them feel more comfortable. My conclusion was not to change—signing “Dr. Bracher” would probably make me feel just as weird as if they were to address their e-mails to “Paul”. Anyway, the decision of what to call myself has got to be one of the few privileges to which I am entitled in this new job.

–Paul