STEM EDX: See Yourself as a Practitioner – Utility Value Assignments

Hannah Sevian (Department of Chemistry)
STEM EDX Fellow, AY 20-21

Overview

The utility value assignment is a type of alternative assessment that is both formative and activist. It aims to affirm students’ values as it creates a mechanism for students to review the learning objectives during the week prior to an exam. The design is based on stereotype threat and cultural mismatch research.

The basic instructions are that students should select a concept or issue that was covered in a unit and formulate a question that is relevant to their own lives or career interests. They select the relevant information from class notes and the textbook, and write a 1–2 page essay. The essay should address the question and discuss the relevance of the concept or issue to the student’s own life. Students are asked to include some concrete information that was covered and will be assessed on the upcoming exam, explaining how the information applies to the student personally using examples.

The researchers who studied the impacts of utility value assignments found that affirming the value of STEM knowledge and capability has a positive impact on closing the social class achievement gap. There is an especially large impact on first-generation college students compared to continuing-generation students [see Harackiewicz et al. 2014]. In the study, the intervention was implemented twice during the semester: at the beginning of the semester, and shortly before the second exam. The authors point out that the activity addresses a reduced sense of belonging. The timing of the intervention in the study suggests that the midpoint of the semester is a time when sense of belonging may be most impacted by a value-affirming activity. The utility value assignment idea can also be used as a component of an exam, but then it loses its effectiveness in preparing students before the exam.

Harackiewicz, Judith M., Elizabeth A. Canning, Yoi Tibbetts, Cynthia J. Giffen, Seth S. Blair, Douglas I. Rouse, and Janet S. Hyde. “Closing the social class achievement gap for first-generation students in undergraduate biology.” Journal of Educational Psychology 106, no. 2 (2014): 375-389.

Description of Activity

I assigned utility value assignments due the Friday before each exam (exams were on Tuesdays). There were five exams during the semester (there was not a final exam, the students did a final project instead). At least one week prior to the due date of each utility assignment, I posted the learning objectives that would be assessed on the upcoming exam. The utility value assignments required students to select one of the learning objectives on which to focus their question and essay.

Students could submit as many attempts as they wanted, until the deadline; only their last attempt was graded. The rubric for grading the assignment was based on 6 points total (only integer points).

  • Pose a useful question that you could answer that uses that topic of chemistry.
    • Up to 2 points: scored based on clarity of the question and how relevant the question is to the topic.
  • Write an explanation of how you would go about answering this question using the chemistry you have learned that is relevant to the topic you chose.
    • 1 point: clarity.
    • 1 point: reasonableness.
    • Up to 2 points: demonstration that you are applying some knowledge of that topic to answering your question – it doesn’t need to be perfect, just reasonable and not totally incorrect.

Some students wrote to ask me if a question that they formulated was along the lines of what I was expecting for the assignment. That opened a really nice opportunity to talk about what the students wanted to get out of this course for their own career goals or to talk about how they saw chemistry as relevant to their daily lives. The most frequent question I got from students was, “How do I know if I get the right answer?” This question gave us the opportunity to talk about how questions in science often do not start with getting the “right” answer. In fact, science is really aimed at addressing questions that we do not yet know the answers, and as you progress further in your undergraduate coursework, you will move more and more toward this kind of work. Right now, this is an assignment where you get to pose a question and then think about how you might begin answering it, using chemistry that you have learned so far. Just like when you do research, you probably will go down some paths that could be dead ends, but you’ll still learn something, and you’ll find out some directions and what more you’d like to learn if you were to work more on addressing the question.

Assignment

Utility Assignment 3 is based on U5M2 [Comparing Gibbs energies] and U5M3 [Understanding mechanism] material. The study guide is located in Blackboard. The goal of a Utility Assignment is to get you started in reviewing the material for the test by connecting it to a question where it is useful to apply chemistry to answer the question. Select a topic that is one of the learning objectives to be assessed on the test. (Students were also provided the grading rubric and an example of a good quality Utility Assignment.)

Most students received scores of 5 or 6 points.

Student 1 Response

Learning Objective 6. Determine the shelf-life of a medication (10% loss of activity) at a particular temperature when given either concentration vs. time data, or the half-life, or the rate constant

Question: Succinylcholine is an intense muscle relaxer used in hospitals for anesthesia purposes. However, too much of succinylcholine can be fatal, this drug must be regulated in refrigerated temperatures and administration via IV. If a doctor accidently misread the labels and switched vials for succinylcholine and did not refrigerator the drug after us, would the half-life of the drug change due to higher temperature exposure?

Answer: (Warning, might be graphic I want to study pathology this is an example of drug abuse and overdose which can lead to death if not used properly)

To begin with this question, first one must know about Succinylcholine. This is a drug for muscle relaxation in the body commonly used right before a surgery in anesthesia purposes. The drug is calculated to injection through the patient’s body weight for the correct amount before fatal. Like most to all drugs, there are side effects which can be hefty. One of the side effects is muscle wasting, though this is a relaxer to the muscles, it can begin to break down the tissues inside the body and begin to damage the muscles leading to complete paralysis and in some cases death. This drug usually is not administered to children for these extreme reasons.

Succinylcholine is stored at 36-46 degrees Fahrenheit which is the average refrigerator temperature that would keep milk cold without spoiling. So why does this matter? There could be a possibility that temperature exposure can breakdown the drug which could lead to the fatal effects if not administrated correctly. Does the temperature have an effect on the drug shelf life and half-life?

An experiment that I would compose would involve animal testing on mice. (Again, sorry this is graphic). The experiment would be based on two sets of mice: one that would be administrated the drug at refrigerator temperatures and monitored and the other that was exposed to room temperatures for over a 12-month period. Normally this drug has a half-life of 10-15 minutes which is a very fast reaction. This makes the drug very hard to trace in blood once it has completed its cycle, the drug leaves the body without a trace.

By setting up this experiment: the two mice need to be monitored within the half-life time of the drug which when properly stored can be 10-15 minutes of paralysis given the correct dose. After calculating the weight of the mice and the two vials exposed, the drug should be injected at the same time for the effects to begin. It could be inferred that the drug will begin to take effect when the mice slowly stop moving or sleep.

Examination of the two mice should be monitored between the original half-life of 10-15 minutes but then closely analyzed for about an hour to record any discrepancies. Experts have determined that Succinylcholine can last up to 6 months exposed to room temperature and sunlight without the shelf life going bad. It can also last up to 2 year if kept refrigerated and stored without sunlight.

The comparison between the two groups of mice can be graphed with the idea of exposure to temperature vs. concentration of the drug administrated. We can plot the change in fatality of the mice by long term exposure to the drug that has not been refrigerated versus the one that has. These results would provide the long-term exposure to succinylcholine and how there would need to be more of the drug administered to the mice that were exposed too room temperature because the half-life of the drug would have been chemically damaged creating it harder for the drug to release its full effects.

Based on what we know about drug half-life, it is the time it takes for the drug concentration to reach 50% capacitation in the body. By testing the variability of the drug’s half-life in the mice we can infer that temperature change has an effect on drugs and the chemical break down that allows the half-life to occur. The theory that the shelf life would be affected is also true based on the long-term exposure of temperature to a drug would have negative effects on the half-life causing more injection to the drug for the same effects that would happen if the drug was refrigerated.

Student 2 Response

Learning Objective 3: Order of rate law determined from concentration vs. time data/graph

Question: How does the change in temperature affect the rate of concentration of orange juice in the orange cake?

Answer: In this question, I need to determine how the rate of concentration will be affected at different temperatures in the orange cake. As well, to determine the reaction rate and to calculate the k value. I need to determine the initial rate of the concentration in orange cake at different temperatures. I must find which of the three temperatures 10oC, 20oC, and 30oC are going to decrease the concentration of the orange juice and how the flavor of the orange cake is going to be affected. As well, to see how the amount of the orange juice concentrate that is reacted is going to affect the size of the orange cake resulting as big or small. Also, I will use the equation, ln[A] = ln[A]o – kt, to calculate the concentration, and to calculate half life the equation, t1/2 = ln 2 / k, needs to be used.

Orange Cake

Vitamin C is acidic in which can cause the orange cake to expand or shrink when is added with the yeast. The more orange juice concentration is added the smaller it gets. The orange juice gives off hydrogen ions when they are being dissolved in water. Having a high concentration of orange juice can affect the main functions of making the cake such as the hydrogen that was being released can interact with other molecules in the solution. The protein alteration can cause the cake to stranger structure like the image above. This is because the hydrogen ions are disrupting the bonds that are keeping the folded protein into a specific shape and it causes them to unravel. The starch in the cake can cause the orange juice to break down at lower temperatures causing the cake to set more quickly and having less structure support, weak. As well, the reaction can cause the orange cake to be paler. The flavor of the orange cake is going to be plain since the concentration is decreased by having a high temperature. If the orange juice had a low concentration, the cake would have a sour flavor.

Ascorbic Acid Concentration

In the picture above it demonstrates that the reaction is first order because of the y axis having rate = k[A]. The graph demonstrates that at temperature 30oC the concentration is decreasing rapidly as the temperature increases meaning that it has the quickest half lifetime. For temperature 20oC, demonstrates that the concentration in the first 48 hours starts at a steady rate, but afterward it began to slow down over time. At temperature 10oC, it had the most concentration but decreasing slowly as the temperature increases. The temperature 10oC, was the best one since the concentration was being reduced slowly. Therefore, high temperature and half lifetime maintain concentration. At low temperature and half lifetime, the concentration decreases.

Calculating reaction rate:

Equation: ln[A] = ln[A]o – kt