Recent advancements in Additive Manufacturing (AM)/3D Printing have influenced a change in object design and production. This has attracted many production industries to adopt the AM technique, resulting in a proportionate need for a workforce skilled in AM. In tandem, AM education has been introduced in schools to develop the AM-skilled workforce. However, inadequate systematic AM education hinders the development of the AM workforce. A review of the literature indicates that there is currently a lack of learning theory integration with AM education implementation. Learning theories provide a basis for understanding how people learn. This research applied both the "constructivism learning theory" and the "Technological Pedagogical Content Knowledge (TPACK) framework" to teach and evaluate students' AM skill development in terms of students' self-efficacy and content knowledge in a freshman-level engineering course at a Historically Black College and University (HBCU). The research methodology involved an Explanatory Sequential mixed method. The instrument used was a previously validated Engineering Skills Assessment developed for engineering undergraduates. Pretest and post-test assessments were given to the students (n =26). Instructors administered Constructivism-structured AM classes throughout the semester. Students were individually assigned to design and 3D-print a miniature boomerang as a course project. Interviews were granted to randomly selected students (n =7). The quantitative data was analyzed using the Wilcoxon Signed-Rank Test. The results of the statistical tests indicated a significant impact of AM exposure on students' self-efficacy and content knowledge. Statistically, students' self-efficacy mean score was increased by 8.04 points, and the content knowledge mean score was increased by 17.38 points. From the interview results, students expressed that their engineering knowledge, skills, and self-efficacy were enhanced after exposure to AM. The findings indicated that adequate AM education has positive impacts on students' self-efficacy and content knowledge and is effective in developing a workforce skilled in AM. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]