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  1. Free, publicly-accessible full text available August 1, 2024
  2. This paper is the culmination of four years of an NSF-funded project implementing and assessing an undergraduate additive manufacturing course at three large state universities: Texas Tech University, Kansas State University, and California State University – Northridge. The research questions addressed are: (1) What are the changes in skill and knowledge concerning additive manufacturing experienced by undergraduate students? (2) What is the effect of this course on attitudes towards engineering and self-efficacy in engineering for enrolled undergraduate students? The sample consists of four years of data from the undergraduate students enrolled in the course at all three universities (combined N = 196). Our method for data collection was matched-pair surveys that contained both (i) an assessment for content knowledge and (ii) an attitudinal assessment previously validated in published research for data collection about attitudes towards engineering. Matched-pair surveys means that we collected data from Student X at Time 1 (before being taught) and then again from at Time 2 (after being taught) and are able to directly compare any change in content knowledge or attitude within the same person. We also collected demographic information to be able to see whether changes in, for example, women differed from those in men. All undergraduates experienced statistically significant increases in content knowledge and additive manufacturing skills. In an intriguing finding, female students outperformed male students, which fits with the research that indicates that engineering courses which emphasize pragmatic and real-world applications, as well as those that use group work, will disproportionately help underserved engineering populations like women and people of color succeed. Fitting with the above finding, undergraduates noted that they perceived that they had increased in teamwork, communication, and computer programming skills. These gains were particularly high in female students and students of color. 
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  3. A novel class of polymers and oligomers of chiral folding chirality has been designed and synthesized, showing structurally compacted triple-column/multiple-layer frameworks. Both uniformed and differentiated aromatic chromophoric units were successfully constructed between naphthyl piers of this framework. Screening monomers, catalysts, and catalytic systems led to the success of asymmetric catalytic Suzuki-Miyaura polycouplings. Enantio- and diastereochemistry were unambiguously determined by X-ray structural analysis and concurrently by comparison with a similar asymmetric induction by the same catalyst in the asymmetric synthesis of a chiral three-layered product. The resulting chiral polymers exhibit intense fluorescence activity in a solid form and solution under specific wavelength irradiation. 
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  4. This paper documents the effects of an additive manufacturing course on two sets of students: (1) the undergraduates who took the course and (2) the middle and high school students who visited our labs. At the time of the conference, nine semesters of data (three years at three schools) will have been collected, as well as data from the middle and high school students who visited our labs. Overall, our research questions were: (1) what is the effect of this course on the content knowledge of (a) enrolled undergraduates and (b) middle and high school students? And (2) what is the effect of this course on the attitudes towards engineering and self-efficacy in engineering for (a) enrolled undergraduates and (b) middle and high school students? To determine the answers, our longitudinal matched-pairs data collection was conducted. In short, as measured by t-test, all students improved on content knowledge (p<.01), but female students improved slightly more than male students (+9.89 versus +9.01, respectively). Undergraduates did not change their minds about the factors that are important in engineering, although they did significantly change their self-efficacy ratings in some skills because of the course. In particular, undergraduates rated themselves higher in teamwork, creativity, and technical skills, which reflect the content and focus of the course. Additionally, we brought multiple field trips of middle and high school students into our labs for outreach. Using a simplified version of the metric described above, we can see that all students improved on content knowledge. 
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  5. This paper documents the effects of an additive manufacturing course on two sets of students: (1) the undergraduates who took the course and (2) the middle and high school students who visited our labs. At the time of the conference, nine semesters of data (three years at three schools) will have been collected, as well as data from the middle and high school students who visited our labs. Overall, our research questions were: (1) what is the effect of this course on the content knowledge of (a) enrolled undergraduates and (b) middle and high school students? And (2) what is the effect of this course on the attitudes towards engineering and self-efficacy in engineering for (a) enrolled undergraduates and (b) middle and high school students? To determine the answers, our longitudinal matched-pairs data collection was conducted. In short, as measured by t-test, all students improved on content knowledge (p less than .01), but female students improved slightly more than male students (+9.89 versus +9.01, respectively). Undergraduates did not change their minds about the factors that are important in engineering, although they did significantly change their self-efficacy ratings in some skills because of the course. In particular, undergraduates rated themselves higher in teamwork, creativity, and technical skills, which reflect the content and focus of the course. Additionally, we brought multiple field trips of middle and high school students into our labs for outreach. Using a simplified version of the metric described above, we can see that all students improved on content knowledge. 
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  6. Additive manufacturing (AM) is prevalent in academic, industrial, and layperson use for the design and creation of objects via joining materials together in a layer upon layer fashion. However, few universities have an undergraduate course dedicated to it. Thus, using NSF IUSE support [grant number redacted for review] from the Exploration and Design Tier of the Engaged Student Learning Track, this project has created and implemented such a course at three large universities: Texas Tech (a Carnegie high research productivity and Hispanic Serving Institution), Kansas State (a Carnegie high research productivity and land grant university) and California State, Northridge (the largest of all the California State campuses and highly ranked in serving underprivileged students). Our research team includes engineering professors and a sociologist trained in assessment and K-12 outreach to determine the effects of the course on the undergraduate and high school students. We are currently in year two of the three years of NSF support. The course focuses on the fundamentals of the three families of prevailing AM processes: extrusion-based, powder-based, and liquid-based, as well as learning about practical solutions to additive manufacturing of common engineering materials including polymers, metals and alloys, ceramics, and composites. It has a lecture plus lab format, in that students learn the fundamentals in a classroom, but then apply and broaden their knowledge in lab projects and independent studies. Additionally, as outreach, we host field trips from local high schools during which the undergraduates give presentations about discrete AM skills, then lead the high school students through a lab project focused on those skills. This creates a pipeline of knowledge about AM for younger students as well as an opportunity for undergraduates to develop leadership and speaking skills while solidifying their knowledge. We are also in the process of uploading videos and lab projects to an online Google Classroom so that those with access to 3D printers in other areas can learn online for free. We are also self-publishing an accompanying textbook and lab manual. Beyond the course itself, one of the innovations of our project is the assessment strategy. For both undergraduates and high school students, we have been able to collect content area knowledge both before and after the class, as well as information about their attitudes towards engineering and self-efficacy beliefs. This has been particularly illuminating in regards to subgroups like women and students of color. Our research questions include: i) what is the knowledge growth about AM during this course? ii) does this differ by university? iii) does this differ by gender or race? iv) what are the best ways to make this course portable to other universities? Preliminary results indicate a statistically significant improvement in knowledge for all students. This was particularly true for women, which may indicate the promise of AM courses in decreasing the female dropout rate in engineering. Attitudes towards engineering and self-efficacy perceptions also differed after the class, but in varying ways by demographic subgroups and university. This will be explored more in the paper. 
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  7. This NSF IUSE project is on the Exploration and Design Tier and the Engaged Student Learning Track. It is aimed at better preparing the country’s professional workforce in the renaissance of U.S. skilled manufacturing by creating new personnel proficient in additive manufacturing (AM). AM is mainstream; it has the potential to bring jobs back to the U.S. and add to the nation’s global competitiveness. AM is the process of joining materials to make objects from 3D data in a layer upon layer fashion. The objectives are to develop, assess, revise, and disseminate an upper division course and laboratory, “Additive Manufacturing,” and to advance undergraduate and K-12 student research and creative inquiry activities as well as faculty expertise at three diverse participating universities: Texas Tech, California State-Northridge, and Kansas State. This research/pedagogical team contains a mechanical engineering professor at each university to develop and teach the course, as well as a sociologist trained in K-12 outreach, course assessment, and human subjects research to accurately determine the effects on K-12 and undergraduate students. The proposed course will cover extrusion-based, liquid-based, and powder-based AM processes. For each technology, fundamentals, applications, and advances will be discussed. Students will learn solutions to AM of polymers, metals, and ceramics. Two lab projects will be built to provide hands-on experiences on a variety of state-of-the-art 3D printers. To stimulate innovation, students will design, fabricate, and measure test parts, and will perform experiments to explore process limits and tackle real world problems. They will also engage K-12 students through video demonstrations and mentorship, thus developing presentation skills. Through the project, different pedagogical techniques and assessment tools will be utilized to assess and improve engineering education at both the undergraduate and K-12 levels through varied techniques: i) undergraduate module lesson plans that are scalable to K-12 levels, ii) short informational video lessons created by undergraduates for K-12 students with accompanying in-person mentorship activities at local high schools and MakerSpaces, iii) pre- and post-test assessments of undergraduates’ and K-12 participating students’ AM knowledge, skills, and perceptions of self-efficacy, and iv) focus groups to learn about student concerns/learning challenges. We will also track students institutionally and into their early careers to learn about their use of AM technology professionally. 
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