Effectiveness of Flipped Classroom for Mechanics of Materials

The flipped classroom is a teaching method that flips the activities done in and out of class, i.e., concepts are learned out of class and problems are worked in class under the supervision of the instructor. Studies have indicated several benefits of the Flipped Classroom (FC), including improved performance and engagement. In the past years, further studies have investigated the benefits of FC in statics, dynamics, and mechanics of materials courses and indicate similar performance benefits. However, these studies address a need for additional studies to validate their results due to the short length of their research or small classroom size. In addition, many of these studies do not measure student attitudes, such as self-efficacy, or the difference in time spent out of class on coursework. The objective of this research is to determine the effectiveness of the flipped classroom system in comparison to the traditional classroom system (TC) in a large mechanics of materials course. Specifically, it aims to measure student performance, student self-efficacy, student attitudes on lecture quality, motivation, attendance, hours spent out of class, practice, and support, and difference in impact between high, middle, and low achieving students. In order to accomplish this, three undergraduate mechanics of materials courses taught during the spring 2015 semester at Arizona State University were analyzed. One FC section served as the experimental group (92 students), while the two TC sections served as the control group (125 students). To analyze student self-efficacy and attitudes, a survey instrument was designed to measure 18 variables and was administered at the end of the semester. Standardized core outcomes were compared between groups to analyze performance. This paper presents the specific course framework used in this FC, detailed results of the quantitative and qualitative analysis, and discussion of strengths and weaknesses. Overall, an overwhelming majority of students were satisfied with FC and would like more of their classes taught using FC. Strengths of this teaching method include greater confidence, better focus, higher satisfaction with practice in class and assistance received from instructors and peers, more freedom to express ideas and questions in class, and less time required outside of class for coursework. Results also suggest that this method has a greater positive impact on high and low achieving students and leads to higher performance. The criticisms made by students focused on lecture videos to have more worked examples. Overall, results suggest that FC is more effective than TC in a large mechanics of materials course. Introduction and Background The Flipped Classroom is a teaching method in which students learn class concepts at home, typically through online videos, and work on assignments in class with the guidance of the instructor. The use of this methodology has become well established and has numerous benefits which include: increased active learning, ability to learn material at one’s convenience, potentially less time spent outside of class on coursework, performance improvements, and increased student-teacher interaction. Although there is large support for the use of FC, there are relatively few research papers that focus on Mechanics of Materials. Three of the studies are fairly inconclusive and are limited by their small sample size. Vogt is conducting an on-going survey study which has included 16 student responses so far and does not include a performance study. Lee et al. conducted performance analysis that indicates improvement, but the significant variability in data and small sample size of 11 and 15 students makes the study inconclusive. Swartz et al. conducted a survey study, which involved 22 students. The only results mentioned in the study state that 15 of the 22 students voted to maintain FC for the second half of the semester. Two strong studies incorporated over 100 students and focused primarily on performance. Ryan et al. found a small performance improvement, but was only able to compare data from the first exam, as the later exams varied greatly between 2013 and 2014. Notably, the percentage of students who scored less than 60% decreased by 7%, hinting that FC benefitted lower achieving students. Last, the study states that the instructor received the highest student course evaluations for overall course quality and instructor effectiveness during the year of the study, but does not mention the previous scores or number of student responses. Thomas et al. conducted an extremely detailed performance analysis on a large sample size, but there was no statistical difference. In summary, there are two performance studies that are promising and one that is inconclusive. In addition, there are no complete studies that measure the other benefits of FC, such as studentteacher interaction, in a Mechanics of Materials course. This study serves to fill in those blanks by measuring student performance, student self-efficacy, student attitudes on lecture quality, motivation, attendance, hours spent out of class, practice, and support, and difference in impact between high, middle, and low achieving students, in a flipped and traditional classroom. Implementation of the Flipped Classroom Three Mechanics of Materials courses taught during the spring 2015 semester at Arizona State University were utilized with 3 different professors, with a total of 217 students. One course was taught using the FC method and served as the experimental group, with 92 students. The two other courses were taught traditionally, with 125 total students. All three courses were taught with two 75-min lectures and a 50-min recitation each week. In this specific FC, students learned the material at home primarily using lecture videos created using Livescribe Pencast PDF. This lecture video was supplemented with PDF lecture notes. Over the course of the semester, 23 sets of Livescribe Pencast PDF and PDF lecture notes were created. In class, students were sorted into groups of four at the beginning of the year. Groups would complete a pre-lecture quiz and group worksheet together. Each worksheet included an average of 4 problems with an extra challenge problem. Quizzes had only 1-2 questions. In order to properly address the questions of the large class size, four teaching aides were present during lecture in addition to the instructor. Over the course of the semester, 24 worksheets and quizzes were assigned. Last, three extra things were done. Five short homework assignments were assigned to provide extra practice and another method to measure performance. Second, a truss project was assigned to each group, in which a 2D truss was to be designed, built, and tested to failure to provide a hands-on application of course concepts. Third, an optional timed practice final exam was made available for students from all three courses to directly compare student performance between the three classes. Research Methodology In order to measure student performance between three distinct classes, standardized course core outcomes were used. This is the accepted concept inventory for Mechanics of Materials at this university and is the only feasible method to compare student performance between three different classes. The five assigned homework assignments, various exam problems, and the problems of the practice final exam align with different core outcomes and were used to measure the performance of each student. Table 1 details how each core outcome was measured. Table 1. Evaluation of Core Outcomes In order to analyze self-efficacy, student attitudes on lecture quality, motivation, attendance, hours spent out of class, practice, and support, and difference in impact between high, middle, and low achieving students, an online survey instrument was designed and administered at the end of the semester to all voluntary students. To determine if the student was high (A), middle (B), or low (C) achieving, the students’ grade from the prerequisite course, engineering mechanics (statics and dynamics), was utilized. An A+, A, or Ain engineering mechanics would categorize a student as a high achieving (A) student for the purposes of this study, as shown in Table 2. Grade point average was considered, but the responses did not allow for an even distribution into three distinct groups. Table 2. Method for Categorizing Students into Achievement Groups The survey instrument is based off of various different studies which measured motivation and self-efficacy. The instrument measures variables of interest using 18 questions and utilizes a 7point Likert scale for each question, except questions 11 and 14. Question 11 deals with lecture attendance and is measured on a scale of 1 to 4, with 1 being lowest attendance. Question 14 Course Core Outcomes Achievement Level Corresponding Assignments Students will understand the definitions of stress and strain, and basic mechanical properties of materials such as elasticity, yielding stress, Young's modulus and Poisson's ratio. Knowledge Homework 1 Exam 1 Students will apply concepts of strain and stress to the analysis of statically-determinate and indeterminate bars under axial loading. Comprehension Homework 2 Exam 2, problem 1 Students will apply concepts of strain and stress to the analysis of statically-determinate and indeterminate shafts in torsion. Comprehension Homework 3 Exam 2, problems 2 & 3 Students will analyze the shear, moment distribution, and calculate stress in beams under bending. Comprehension Homework 4 Exam 3, problem 1 Students will predict deflection in beams under bending and analyze statically indeterminate beams. Comprehension Homework 5 Exam 3, problems 2 & 3 A+ A AB+ B BC+ C CEngineering Mechanics Grade High Achieving (A) Middle Achieving (B) Low Achieving (C) deals with time spent on coursework outside of class and is measured in number of hours, r