(196h) Teaching Principles of Biomaterials during the COVID-19 Pandemic with at-Home Inquiry-Based Learning Laboratory Experiments
AIChE Annual Meeting
2021
2021 Annual Meeting
Education Division
Free Forum on Engineering Education: Special Topics, Unique Modules, and Research-Based Electives
Monday, November 8, 2021 - 5:36pm to 5:54pm
Methods: Three at-home laboratory experiments were created to teach students principles of Ceramic Toughness, Metal Corrosion and Polymer Stiffness. Materials were purchased from Amazon and shipped directly to students. The total supplies for all three experiments cost less than $100 per student. Additionally, students were taught to use R, ImageJ and Tracker software, which are all open-access software packages commonly used in the biomaterials field. With these tools, laboratory groups completed an inquiry-based pre-laboratory exercise, which helped students brainstorm the exact parameters they planned to test. After in-class discussion, teams were required to submit a written pre-laboratory report that explained the independent variables they were studying, described their methods of quantifiably testing the materials, and calculated a statistically appropriate sample size. After receiving instructor feedback, students had 3-10 weeks to collaboratively complete their experiment and submit a final report.
To assess the learning outcomes of these experiments, pre- and post-tests were given for each experiment. A paired Student’s t-test (p < 0.05) was used to compare the average pre-/post-test scores. Additionally, an end of semester survey was given to evaluate how the student’s perceived the at-home experiments. Descriptive statistics were used to assess the survey results. All surveys were approved by The Cooper Union Institutional Review Board (IRB).
Results: Students successfully completed all three at-home experiments with virtual instruction. For the Ceramic Toughness Experiment, students created various cement slabs by adjusting the porosity of the material. Students then devised an impact testing scheme and quantified the cement shattering patterns using ImageJ. Significant differences in cement breaking patterns were quantified using statistical analysis in R. Twenty students (N=20) participated in the pre/post-test assessment for the Ceramic Toughness Experiment and the average scores significantly increased from 57.5% on the pre-test to 70.0% on the post-test assessment (Figure 1A).
For the Metal Corrosion Experiment, students tested the effects of many biologically-relevant variables that they could devise in their own homes on the corrosion of paperclips. Over the course of 5-10 weeks, Students studied the effects of variables such as galvanization, salinity, and pH. Students were then charged with devising a fatigue testing scheme to assess corrosion differences quantitatively and identify any significant trends using statistical analysis in R. Twenty-one students (N=21) participated in the pre/post-test assessments for the Metal Corrosion Experiment and the average scores increased from 55.6% on the pre-test to 61.1% on the post-test assessment (Figure 1B).
For the Polymer Stiffness Experiment, students created physically entangled hydrogel cubes from gelatin solutions of varying concentrations. As an added layer of complexity, students were also asked to create gelatin beads to seed into the cubes and form hydrogel composites. Students explored how altering the concentration of gelatin in the pre-crosslinked polymer solution for the bulk cube or beads impacted compressive properties. Students were challenged to devise their own reliable method to test the compressive strength of the bulk cubes and cube/bead composites. To accurately measure compressive hydrogel displacement, students used Tracker software and identified any statistically significant differences using R. Eighteen students (N=18) participated in the pre/post-test assessments for this laboratory activity and the average scores increased from 55.6% on the pre-test to 64.8% on the post-test assessment with trending significance (Figure 1C).
In addition to positive learning gains for all experiments, the results of the end of semester survey demonstrated that students enjoyed the educational experience. Twenty students (n=20) completed the end of semester survey and a majority of students felt that experiments were easily conducted at home in virtual laboratory groups, effectively taught principles of experimental design and data analysis, enhanced course satisfaction and improved learning more than theoretical problem sets would have. Approximately half the students agreed that completing at-home experiments helped develop their comprehension of metal, ceramic, and polymeric biomaterials.
Discussion: This study demonstrated that at-home inquiry-based learning experiments with virtual instruction are an effective way to teach engineering principles during the COVID-19 pandemic. Based on our pre/post-test assessments, we found that students who completed the at-home experiments had positive average learning gains of up to 12.5 points. For comparison, learning gains of approximately 10-15 points were measured for a set of traditional laboratory experiments. [2] Results therefore suggest that the proposed at-home experiments are an alternative to traditional laboratory experiments given the constraints of the COVID-19 pandemic with comparable improvements in comprehension and student engagement.
Based on the end of semester survey results, students welcomed the chance for hands-on experiences while they were unable to have in-person instruction. Other student feedback noted that some students felt that having three inquiry-based learning experiments was overwhelming. The approach of inquiry-based learning, which requires the students to take a more active role in the creation of the laboratory experience, is more time-consuming than traditional teaching approaches. [6] This should be a consideration for educators in the use or creation of other at-home experimental modules. Additionally, the ability to safely and effectively run experiments at-home at a low cost has further implications on expanding access for STEM outreach more broadly.
Outreach is an important activity for increasing the number of students studying STEM and to reach those who are traditionally underrepresented in STEM-based on race, ethnicity, gender, sexual orientation, socioeconomic status, etc. [7]–[9] To help the widespread efforts to promote STEM in these communities, we adapted our Metal Corrosion Experiment to an outreach activity run over two sessions with the Young Eisner Scholars (YES) Program. YES is a program designed to empower middle and high school students from underserved communities. Using pre/post-experiment evaluations, we found that middle school students had significant learning gains and increased positivity towards science after completing our activity. Overall, we hope that these experiments are useful for biomaterials educators and, more broadly, inspire chemical engineering educators to devise creative, at-home experiments for their students due to COVID-19, other disruptions to the traditional, in-person learning environment, and beyond in experiences such as STEM outreach.
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