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By Catherine LaMoreaux January 6, 2020

Paula Mazzer, PhD

Paula Mazzer, PhD, considers her Analytical Chemistry course the point at which professors transition students from having their hands held to being tossed into the lab without swim fins. It is a fitting analogy coming from a woman who once wanted to be an ichthyologist-and a fitting goal for students who will need to conduct independent lab work in upper-level courses and in careers post graduation.

The class is part of a four-course, four-semester sequence at Dakota Wesleyan University in Mitchell, South Dakota, which the Biochemistry Department (including Mazzer) designed to gradually build skills in independent lab work. Its intent: to break through students frustration when they hit a roadblock and lack the confidence to proceed-what professors refer to as the Sophomore Syndrome.

By the time they take her Analytical Chemistry course-the final one in the series-Mazzers students already have the tools and skills necessary to do research, write about science, and record their findings-all of the more objective aspects of lab work. This is a natural progression, and the next step-analytical thinking-is one they are prepared (and need) to take.

Mazzer wanted to add her own twist by showing students that analytical thinking can actually be fun -that it is a skill you can build if you practice. To create a curriculum that fit all these criteria, she had to do some analytical thinking of her own.

Challenge

Students are used to doing labs with directions

Before they start the four-course sequence, students have been completing what Mazzer calls cookbook-type labs, in which they are given a problem and the steps to follow. To enable them to learn to figure out the steps for themselves, she wanted to provide a safe and supportive space where they would have plenty of opportunities for trial and error. On the flip side, she wanted the course to be rigorous enough to challenge them in ways that would mimic post-graduation lab work.

Innovation

Approach analytical thinking with an eye for fun

Mazzer structured her Analytical Chemistry class around three activities that build on one another to prepare students to conduct three independent (and very interesting) labs. She begins by giving them a lesson in all-important risk assessment. They then get some quality time with relevant lab machines, learning to master their use. Finally, she presents them with a question box of index cards presenting quirky and interesting chemistry problems, which serve as the starting points for their independent lab experiments. (One compelling example: Find out how much of the chemical rotenone is in various organic products sold locally.)

Context

By the end of this course, students are much more willing to think on their feet and much more willing to troubleshoot. They understand what theyre doing better. And they dont get back reports that say lab failed.

- Paula Mazzer, PhD

Course: CHM 323 Qualitative and Quantitative Analysis

Course description: Students will study quantitative analytical methods, principles, details and applications, including the statistical treatment of data. Lab exercises cover the qualitative analysis scheme in the first half of the semester and more specific analytical problems in the second half. Three lectures, one three-hour laboratory plus extra lab hours by arrangement.

See and share lecture notes, practice tests, and teaching materials.

3 steps to turn chem students into independent chemists

Mazzer has found that the following three-step approach has made a huge difference in preparing students for independent research. Before, students would say, Just tell me what to do, and Ill do it. In fact, when she first floated the idea of developing and running their own experiments, Mazzer said students initially looked at her with that deer in the headlights stare. By the end of the semester, though, they are ready for the spotlight-and a real job.

Step 1: Risk assessments

Mazzer starts the course off with a lesson on risk management in the chemistry lab. She reminds students that they must wear goggles and gloves at all times, but beyond that, they also must be aware of the hazards of the chemicals they are using. Mazzer walks them through the process that all professionals follow. The steps include:

Researching inherent risksVisualizing the activityBrainstorming potential problemsFinding ways to mitigate risks that can be mitigatedAddressing the problems that cannot be mitigated

Next, the class puts the risk management strategy into practice: Mazzer tells them to pretend they have to boil water. They discuss the risk assessment steps with the student next to them, brainstorming everything that could go wrong and how to prevent those things from happening. Many of the risks they envision-such as being burned-are the hazards inherent in chemistry labs.

Once students understand the process, Mazzer tells them that they will need to do risk management for every experiment they undertake. Just as in the exercise, they will talk through all of the possible dangers with a classmate, who will provide them with feedback, then sign off to indicate that their peer has completed their risk assessment for that activity.

Step 2: Checklists

Before students begin experimenting, they will need to familiarize themselves with the lab equipment. To do this, Mazzer has them complete what she calls Checklist Labs.

There is one Checklist Lab for each of the eight pieces of equipment that they will need to be able to use for their experiments. The machines include a spectroscope, a gas chromatography-mass spectrometer, and a nuclear magnetic resonance device. They can complete the labs in any order, with or without a partner.

For each Checklist Lab, students begin by reading the guidebook Mazzer provides for that instrument, as well as an analytical book with steps on how to use it. Then they work through the checklist itself, which describes the activity students will do with the machine and the evidence they need to produce to show that they have learned to use it. For instance, they may run an unknown substance through a machine to identify it, then provide a chromatogram as evidence, and finally write two or three paragraphs about the process.

The activities are simple, but the students enjoy the autonomy they have in completing them. Mazzer is there to help and answer questions, but her goal is to build students independence, so she is as hands-off as possible. After the Checklist Labs, Mazzer says that students find the equipment not quite as scary.

Step 3: The Question Box

With students ready for their first independent lab work, Mazzer presents the class with a Question Box that holds cards in three different colors:

Green cards have qualitative questions (example: Determine which drinks have the most caffeine).Yellow cards have quantitative questions (example: Find the chemical difference between bottled and freshly grated horseradish).Red cards have questions that require advanced separation skills (example: Extract lycopene from different types of tomatoes).

Mazzer chose the colors to emphasize how hard she believes the various choices are, but students may work on them in any order.

They must complete one card of each color-three in total-using the risk assessment steps and the equipment from the Checklist Lab. Students sift through the cards to find ones that interest them, or they can create one of their own, with Mazzers approval. Most start with a quantitative or qualitative question and leave the separation assignment for last, since it is the toughest category. (With just three lab reports per student to grade, this approach also saves time over the usual lab-a-week approach of most science courses.)

The questions are actually prompts for a larger, professional-grade research assignment: First the students refine the broad question theyve chosen, which often begins with something such as, How much caffeine is in your favorite drinks? They narrow the scope of the question-what drinks do they want to test, how much do they define as how much (per cup, per serving, per ounce)? They then research the topic in the scientific literature, formulate a hypothesis, and develop and run an experiment.

They work alone, at their own pace, and are given a month to answer each question. Once they finish one experiment, they write up the results, turn in their lab reports, and move on to the next card-just like a professional scientist.

Outcomes

Mazzer says there have been some beautifully interesting reports turned in. She cites one example in which a student developed a quantitative question from the box into an experiment on a local reservoir, analyzing how many nutrients and pollutants are in the creek that feeds it. The student found a map of the area and pinpointed places she could sample the water. That student has since gone on to work for the South Dakota Department of Game, Fish, and Parks-one result that officially validates this teaching experiment.

Originally published at https://www.coursehero.com on January 6, 2020.