On flipping the classroom in large first year calculus courses

Over the course of two years, 2012--2014, we have implemented a ‘flipping’ the classroom approach in three of our large enrolment first year calculus courses: differential and integral calculus for scientists and engineers. In this article we describe the details of our particular approach and share with the reader some experiences of both instructors and students.     

The impact of instructor pedagogy on college calculus students’ attitude toward mathematics

College calculus teaches students important mathematical concepts and skills. The course also has a substantial impact on students’ attitude toward mathematics, affecting their career aspirations and desires to take more mathematics. This national US study of 3103 students at 123 colleges and universities tracks changes in students’ attitudes toward mathematics during a ‘mainstream’ calculus course while controlling for student backgrounds. The attitude measure combines students’ self-ratings of their mathematics confidence, interest in, and enjoyment of mathematics. Three major kinds of instructor pedagogy, identified through the factor analysis of 61 student-reported variables, are investigated for impact on student attitude as follows: (1) instructors who employ generally accepted ‘good teaching’ practices (e.g. clarity in presentation and answering questions, useful homework, fair exams, help outside of class) are found to have the most positive impact, particularly with students who began with a weaker initial attitude. (2) Use of educational ‘technology’ (e.g. graphing calculators, for demonstrations, in homework), on average, is found to have no impact on attitudes, except when used by graduate student instructors, which negatively affects students’ attitudes towards mathematics. (3) ‘Ambitious teaching’ (e.g. group work, word problems, ‘flipped’ reading, student explanations of thinking) has a small negative impact on student attitudes, while being a relatively more constructive influence only on students who already enjoyed a positive attitude toward mathematics and in classrooms with a large number of students. This study provides support for efforts to improve calculus teaching through the training of faculty and graduate students to use traditional ‘good teaching’ practices through professional development workshops and courses. As currently implemented, technology and ambitious pedagogical practices, while no doubt effective in certain classrooms, do not appear to have a reliable, positive impact on student attitudes toward mathematics.     

Stabilization and set stabilization of switched Boolean control networks via flipping mechanism

Stabilization and set stabilization of switched Boolean control networks are investigated by using flipping mechanism in this paper. Firstly, with the help of Warshall algorithm, an explicit criterion for the stabilization of switched Boolean control networks is derived. Secondly, the necessary and sufficient condition for the solvability of stabilization of switched Boolean control networks, by flipping some elements of perturbation set once, is presented. Thirdly, a search algorithm is proposed to calculate the minimum number of stabilization flipped nodes and what exactly they are. Furthermore, a necessary and sufficient condition is established for the solvability of set stabilization of switched Boolean control networks by flipping some elements of perturbation set once. Analogously, an algorithm is given to find the minimum number of set stabilization flipped nodes. Finally, examples are shown to demonstrate the feasibility of the above results.     

The impact of taking a college pre-calculus course on students’ college calculus performance

Poor performance on placement exams keeps many US students who pursue a STEM (science, technology, engineering, mathematics) career from enrolling directly in college calculus. Instead, they must take a pre-calculus course that aims to better prepare them for later calculus coursework. In the USA, enrollment in pre-calculus courses in two- and four-year colleges continues to grow, and these courses are well-populated with students who already took pre-calculus in high school. We examine student performance in college calculus, using regression discontinuity to estimate the effects of taking college pre-calculus or not, in a national US sample of 5507 students at 132 institutions. We find that students who take college pre-calculus do not earn higher calculus grades.     

Instantaneous rate of change: a numerical approach

The calculus reform movement has encouraged numerical and graphical approaches to functions in addition to the more traditional analytical approach. While valiant efforts have been made to use these other approaches in newer calculus curricula, more numerical approaches should be introduced. Research on student learning in calculus indicates that particular numerical approaches hold promise for students' learning of instantaneous rate of change. Numerical approaches involving the average rate of change over successively smaller intervals can be used to obtain the instantaneous rate of change for a given function at a given value of x. These approaches can help students appreciate the fundamental relationship between average and instantaneous rates of change. They can also be used to obtain general expressions for the derivative of most elementary functions. Standard computer spreadsheet programs facilitate this process and make numerical approaches a more viable option for calculus instruction. These are underutilized resources for instruction in calculus, even in reform or other new calculus curricula.     

离散数学的翻转课堂教学法研究

离散数学是计算机专业的重要的基础课程.但是离散数学课程抽象难懂、教学模式单一、理论实际结合能力差,从而影响了这一课程的教学效果.为了提升离散数学的教学效果,面向学生翻转课堂的教学模式被引入.翻转课堂通过视频、示例或者项目、以及拓展等方式充分发挥学生为中心,教师辅助的教学理念,提升学生学习的主动性,提升离散数学的教学效果,为后续计算机专业课程奠定良好的基础.     

Tensor calculus: unlearning vector calculus

Tensor calculus is critical in the study of the vector calculus of the surface of a body. Indeed, tensor calculus is a natural step-up for vector calculus. This paper presents some pitfalls of a traditional course in vector calculus in transitioning to tensor calculus. We show how a deeper emphasis on traditional topics such as the Jacobian can serve as a bridge for vector calculus into tensor calculus.     

Retention of differential and integral calculus: a case study of a university student in physical chemistry

This paper reports a study on retention of differential and integral calculus concepts of a second-year student of physical chemistry at a Danish university. The focus was on what knowledge the student retained 14 months after the course and on what effect beliefs about mathematics had on the retention. We argue that if a student can quickly reconstruct the knowledge, given a few hints, this is just as good as retention. The study was conducted using a mixed method approach investigating students’ knowledge in three worlds of mathematics. The results showed that the student had a very low retention of concepts, even after hints. However, after completing the calculus course, the student had successfully used calculus in a physical chemistry study programme. Hence, using calculus in new contexts does not in itself strengthen the original calculus learnt; they appeared as disjoint bodies of knowledge.     

Student Interest in Engineering Design‐Based Science

Current reform efforts in science education around the world call on teachers to use integrated approaches to teach science. As a part of such reform efforts in the United States, engineering practices and engineering design have been identified in K–12 science education standards. However, there is relatively little is known about effective ways of teaching science through engineering design. The study explores the approaches or strategies used by a sixth grade science teacher to teach science and engineering in an integrative manner. Classroom observations, teacher interview, and student surveys were used to study the features of engineering integration implemented by the teacher and the changes in student interest in science and engineering by participating in an engineering design‐based science unit. Findings suggest that the teacher explicitly included practices and core ideas from engineering and science; used an engaging, motivating engineering challenge; and provided students with opportunities to be autonomous. Students engaged in the activities in the engineering unit and their interest level slightly increased. The results suggest that the three strategies that the teacher used to teach engineering and science are important foundations of integrated science and engineering education.     

Optimal cell flipping to minimize channel density in VLSI design and pseudo-Boolean optimization

Cell flipping in VLSI design is an operation in which some of the cells are replaced with their “mirror images” with respect to a vertical axis, while keeping them in the same slot. After the placement of all the cells, one can apply cell flipping in order to further decrease the total area, approximating this objective by minimizing total wire length, channel width, etc. However, finding an optimal set of cells to be flipped is usually a difficult problem. In this paper we show that cell flipping can be efficiently applied to minimize channel density in the standard cell technology. We show that an optimal flipping pattern can be found in O(p(n/c)^c) time, where n, p and c denote the number of nets, pins and channels, respectively. Moreover, in the one channel case (i.e. when c = 1) the cell flipping problem can be solved in O(p log n) time. For the multi-channel case we present both an exact enumeration scheme and a mixed-integer program that generates an approximate solution very quickly. We present computational results on examples up to 139 channels and 65000 cells.     

A Study of Student Engagement in Project‐Based Learning Across Multiple Approaches to STEM Education Programs

Objective: In this study, we investigated the implementation of project‐based learning (PBL) activities in four secondary science, technology, engineering, and mathematics (STEM) education settings to examine the impact of inquiry based instructional practices on student learning. Method: Direct classroom observations were conducted during the 2013–2014 school year in STEM Traditional Courses, a STEM Platform School, an Engineering Optional Program (EOP), and a Virtual STEM Academy (VSA) to measure teacher instructional practices (School Observation Measure) and student engagement (The Rubric for Student‐Centered Activities). Results: The four approaches to STEM education showed significant differences in their implementation of PBL, with the EOP and VSA having higher incidences of PBL activities. Additionally, higher‐level questioning strategies, higher‐order instructional feedback, and integration of STEM subject areas was absent or rarely observed. Conclusions: Components of PBL are missing in STEM education, in traditional and non‐traditional STEM courses. In‐service teachers may benefit from professional development that enhances their understanding of PBL activities to maximize student learning opportunities.     

Factoring 111 ... 11 — A stimulating problem

The problem of factoring numbers like 111, 111, 111, 111 is a very productive one. It is beguiling, for in spite of its trivial appearance, this factoring problem leads immediately to considerations of the algebra of polynomials, ring homomorphisms, roots of unity, programming, repeating decimals, and recreational mathematics. This article shows how a pre‐calculus class can be introduced naturally to such ideas. Many of these applications are traditionally considered advanced, and will reappear in a student's curriculum.

A table of 56 factorizations is presented ; the largest is R45 =111, 111, ..., ..., 111. The article follows with an annotated list of applications of the factoring problem (focusing on 111, 111, 111, 111), which have been used successfully with pre‐calculus students. The techniques and comments are geared to the teacher of such a course.     

Authority in an agency-centered, inquiry-based university calculus classroom

Authority roles among teachers and students have traditionally been hierarchal and centered with the expertise and power of the teacher limiting opportunities for students to act with autonomy to build and justify mathematics. In this paper we discuss authority roles for teachers and students that have been realized in an inquiry-based university, honors calculus classroom. We define and discuss four types of authority we identified from video data: institutional, expertise, mathematical, and performative. We suggest that the institutional authority of the instructor is present whether or not she is acting with the intention to bear authority, thereby interfering with the instructor's ability to share authority with her students. Further, we believe that the traditional focus on the bearer of authority limits our ability to create environments wherein authority can be shared. Instead we suggest that a focus on empowering the receiver to recognize expertise and mathematical authorities may be more fruitful.     

Productive and ineffective efforts: how student effort in high school mathematics relates to college calculus success

Relativizing the popular belief that student effort is the key to success, this article finds that effort in the most advanced mathematics course in US high schools is not consistently associated with college calculus performance. We distinguish two types of student effort: productive and ineffective efforts. Whereas the former carries the commonly expected benefits, the latter is associated with negative consequences. Time spent reading the course text in US high schools was negatively related to college calculus performance. Daily study time, however, was found to be either a productive or an ineffective effort, depending on the level of high school mathematics course and the student's performance in it.     

Characterization of curriculum materials to support NGSS-aligned engineering instruction in chemistry teaching

Curriculum materials can play a major role in shaping teachers’ thinking about instruction and content as well as serve as a support for teachers’ learning. With the inclusion of engineering in NGSS, many teachers may be turning to existing curriculum materials to help them infuse engineering into their science classroom, especially when they do not have the time or opportunity for professional development sessions. In this study, we identified a sample of curriculum materials freely available online to chemistry teachers trying to incorporate engineering in the topics of stoichiometry and/or energy, common topics in secondary chemistry curricula. Using qualitative coding methods, we examined what this sample had to offer the chemistry teachers in the way of developing their understanding of engineering and teaching it. Our findings indicate that within our sample there are limited existing curriculum materials to support teachers’ engineering incorporation into secondary chemistry, and the support for teachers varied in terms of content and usefulness across the materials. The materials provided procedural information for activities but lacked in supports for teacher learning and student development beyond the procedure. Implications for the enactment of NGSS in secondary science along with needs for curriculum development and teacher learning are discussed.     

An incentivized early remediation program in Calculus I

Strong prerequisite skills are essential to student success in the calculus sequence; however, many students arrive in Calculus I with weaknesses that are difficult for them to overcome. In this paper, we describe an approach to early incentivized remediation of prerequisite material in a Calculus I course. We present data that supports the idea that a lack of prerequisite knowledge is a significant hurdle for students, but also that participation in the remediation program is correlated with student success. In addition, the program allows for the very early identification of students at high risk of failing. The program is easy to implement, and it would be adaptable to a variety of other courses for which prerequisite knowledge is essential for success including science courses, engineering courses and other mathematics courses.     

Impact of first-year mathematics study groups on the retention and graduation of engineering students

Many interventions have been proposed to improve the retention and graduation rates of engineering students. One such intervention is to use study groups for first-year college students; such groups provide a structured environment in which the students can learn course material from each other outside of class and can provide the students with a sense of community. In this paper, we report on the impacts fostered by study groups in first-year mathematics courses on the odds of retaining and graduating engineering students. Students who participated in the study groups are compared to students of similar academic preparation who did not participate in such groups. It is found that student participation in study groups is significantly associated with the higher odds of being retained in engineering studies through the first 3 years of college. The results reported here are not as certain for the effect of study group participation on 5-year graduation odds for engineering students and some possible reasons for this are discussed.     

The mathematics textbook at tertiary level as curriculum material – exploring the teacher's decision-making process

This paper reports on a study about how the mathematics textbook was perceived and used by the teacher in the context of a calculus part of a basic mathematics course for first-year engineering students. The focus was on the teacher's choices and the use of definitions, examples and exercises in a sequence of lectures introducing the derivative concept. Data were collected during observations of lectures and an interview, and informal talks with the teacher. The introduction and the treatment of the derivative as proposed by the teacher during the lectures were analysed in relation to the results of the content text analysis of the textbook. The teacher's decisions were explored through the lens of intended learning goals for engineering students taking the mathematics course. The results showed that the sequence of concepts and the formal introduction of the derivative as proposed by the textbook were closely followed during the lectures. The examples and tasks offered to the students focused strongly on procedural knowledge. Although the textbook proposes both examples and exercises that promote conceptual knowledge, these opportunities were not fully utilized during the observed lectures. Possible reasons for the teacher's choices and decisions are discussed.