Lecture Video: Characteristics and Utilizations as ... - ACS Publications

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Lecture Video: Characteristics and Utilizations as an Online Learning Resource Downloaded by UNIV OF FLORIDA on November 1, 2017 | http://pubs.acs.org Publication Date (Web): October 26, 2017 | doi: 10.1021/bk-2017-1261.ch008

Pamela L. Mosley* Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, United States *E-mail: [email protected].

Within many areas of higher education, online resources such as lecture videos or recorded webcasts have become part of the classroom environment. This book chapter provides a summary of the findings from research studies focused on the incorporation of online lecture videos in undergraduate courses and the impact these tools have on student learning. There are both benefits and challenges associated with lecture video usage. Key reported benefits include increased learning performance, elevated attention and motivation, improved study habits, and control over learning. Some of the identified challenges include reduced class attendance and the amount of time an instructor must invest in order to create the videos. Overall, while there are limitations, the inclusion of lecture videos in courses seems to be widely favored by students and appears to offer value to their learning experience.

Introduction Over the past decade, lecture videos have grown in popularity within higher education institutions, and they are perceived to be a powerful teaching medium when used appropriately (1). Increased student accessibility to computers and smart mobile devices, the lower cost of lecture video technology, and greater availability of internet bandwidth are all factors that have faciltated change in the direction and frequency of lecture video use and made video implementation in © 2017 American Chemical Society Sörensen and Canelas; Online Approaches to Chemical Education ACS Symposium Series; American Chemical Society: Washington, DC, 2017.

Downloaded by UNIV OF FLORIDA on November 1, 2017 | http://pubs.acs.org Publication Date (Web): October 26, 2017 | doi: 10.1021/bk-2017-1261.ch008

coursework more viable than in the past (2). According to the Campus Computing Project, approximately 80% of public university leaders consider lecture videos a vital part of their campus plan (3). According to the media richness theory, different media have different degrees of richness based on their ability to reproduce the information transmitted over them (4). Video is considered a rich medium. One reason why video constitutes such a rich medium in online learning is that it can present information in an attractive manner. Also, videos are media rich because they are able to transmit a variety of information including language nuances and verbal cues as well as picture, text, and animations. Plus, in some cases, videos provide a way to expose students to things they would not otherwise have the opportunity to see such as different lab techniques, rotating representations of molecules, or animations of atomic or molecular motion or charge transfer (5). Furthermore, videos allow a geographically movable and zoomed in classroom experience. For example, videos can allow students to zoom in on demonstrations which would be more difficult to do in a large lecture hall, they can provide the ability to experience field trips which could be hard to arrange financially and logistically, and they give the instructor the chance to show visting speakers who may have been challenging or expensive to invite (6). Lecture videos or recorded webcasts refer to audio-visual files that are distributed in a digital format through the internet and can be accessed using electronic devices such as personal computers and mobile phones and tablets (7). Some faculty use lecture videos produced by different sources such as Khan Academy or BozemanScience. Others create their own videos using the vast variety of software packages available such as Camtasia and PaperShow or apps on the iPad such as Educreations (8). In a very simple setup, a lecture video can be created by just pointing a video camera towards the front of the lecture hall to capture the instructor, their Power Point slides and voice. A more advanced setup can involve recording the instructor and displaying their Power Point slides along side in a separate frame. In some cases, lecture videos can also capture the instructor writing on a whiteboard, blackboard, or lightboard and include interactive quizzes and demonstrations as well. Thus, a video can be made in one style or it can be edited to contain multiple production styles. How an instructor designs their video is important and has been found to have an impact on student engagement and learning performance (9, 10). Unfortunately, the quality of faculty-created videos vary from magical to marginal, and creating high quality videos does require a significant investment of time. Nevertheless, emerging technology continues to make it easier for lecturers to make their own videos (8). Lecture videos serve a variety of different needs in different contexts. Not only can lecture videos be used to record and distribute lectures as primary content delivery or for general review purposes (3, 11–13) but they can also be used to provide worked examples of problems (14, 15) and act as course supplementary material (16, 17). Lecture videos of worked examples provide explanations of particular problem types that students need to solve in the course. Supplemental lecture videos act as additional resources and help enhance student understanding of the course content. The “flipped” or “inverted” classroom model uses lecture videos to deliver lecture recordings before in-person class meetings to conserve 92 Sörensen and Canelas; Online Approaches to Chemical Education ACS Symposium Series; American Chemical Society: Washington, DC, 2017.


class time for interactive learning activities (18, 19). The flipped classroom is a pedagogical method, which involves flipping or switching what is normally done in class and what is normally done as homework. However, the flipped classroom is more than just a re-ordering of classroom and at-home activities. Instead of students listening to the instructor lecture on a certain concept in class and working on a set of assigned problems at home, lecture videos and practice problems are usually both assigned as homework to be completed before coming to class, and then active, group-based/open-ended problem solving activities are done in the classroom. Thus, the flipped classroom actually represents an expansion of the curriculum, rather than a mere rearrangement of activities. Other approaches to learning that heavily rely on the use of lectures videos are blended courses and online courses including massive open online courses (MOOCs) (8, 20). In the blended or flipped approaches, lecture videos are used to supplement or prepare students for traditional real-time, in-class classroom activities, while for completely online courses such as MOOCs, on the other hand, the lecture videos and associated assignments are often the primary modes instruction. In general, the available literature about lecture videos is quite enthusiastic about the many potentials of these tools. Studies suggest that providing students with lecture videos of course content supports student learning in various ways. However, there are also studies that point out the disadvantages of lecture videos and suggest that their effects on academic performance are contradictory. This review explores the research on the use of science and mathematics lecture videos in general with some specific examples of chemistry videos and their influence on student learning. Both the benefits and challenges of using lecture video as a learning tool will be discussed.

Results and Discussion: Reported Studies of Lecture Videos In chemistry, biology, physics, and even non-science subjects, many of the concepts taught concern phenomenon that we cannot see with the naked eye. As an illustration, chemistry operates on both a macroscopic level, the level dealing with the properties of large, visible objects, and the microscopic level, a world that we cannot see directly, dealing with phenomena like atomic and molecular structure and the rearrangement of atoms during reactions. So, students are often learning about matter and processes that they cannot actually see; instead, they can only create mental images by interpretating representations such as drawings on a piece of paper or diagrams in a textbook. Thus, instead of just providing content, lecture videos can also be beneficial by grabbing a student’s attention and motivating him or her to learn about the unseen microscopic phenomenon that drives a macroscopic process they can observe. For example, showing a clip of what happens to water molecules when you boil water on the stove at the start of a lesson can stimulate discussion and demonstrate the revelance of the topic to the students’ own lives. There are several studies that highlight the student-perceived benefits of using lecture videos (see Table 1). Various studies that incorporated surveys asked students about why they used lecture videos. Three top reasons were reported: 93 Sörensen and Canelas; Online Approaches to Chemical Education ACS Symposium Series; American Chemical Society: Washington, DC, 2017.


improving content retention, control over learning, and making up for missed lectures. The principal reason cited for using lecture videos was to improve content retention which involved using the videos to review for upcoming test or exams (21), preparing for class (22), and taking more thorough notes (23). Many studies in the literature demonstrate that students do enjoy being able to view the videos at their own pace (24, 25) and agreed that videos are beneficial for catching up on classes when they were not able to attend for various reasons or had to travel a considerable distance to attend class (26). With respect to study habits and learning, lecture video use seems to have a constructive impact. McCombs and coworkers observed that lecture videos promote thinking outside of the classroom and have a positive impact on student behavior (8, 27). In addition, the availability of online videos helps to promote more well-organized test and exam preparation (27) and increases behavior such as reviewing the course material during self-study (28). These studies indicate that students used the lecture videos often and spent considerable time watching them. These videos in particular were used for both full course content delivery and as a supplement to lecture content to facilitate student learning. Copey et al. found that lecture videos appear to aid in a student’s understanding of confusing material by allowing the student to review the lecture as often as they want, whenever they want (23). Harpp et al. observed that students are less anxious when they watch lecture videos at their own pace because they do not worry that they will miss information while taking notes (29). There are several types of viewing behaviors observed across different studies in the literature. For example, Traphagan et al. noted students preferred to look at an entire lecture video as opposed to watching certain segements of it (30). Their study used two sections of a large enrollment geology course at a large southwestern university where students in one section were allowed access to lecture videos while the other section was not. Studies such as this one guide instructors to deploy a series of several relatively short (4-10 minute) videos, when possible, rather than a single, longer video on the timescale of a lecture class. On the other hand, Foertch et al. observed that students liked to stop the video at certain points to take notes (31). It is clear that viewing style is not consistent and appears to change based on the cognitive load demands and unique learning style of the individual student. Some research suggests that the way in which a lecture video is designed can help reduce unnecessary cognitive load (32). For example, signaling (which is also know as cueing) (33) is the use of on-screen text or symbols to emphasize important information. Emphasizing key information helps direct learner attention and target particular elements of the video for processing in the working memory. This can reduce extraneous cognitive load because it helps the learner determine which elements within a complex tool or diagram are important. Both Mayer and Moreno (32) and Koning et al. (33) have shown signaling improves student ability to retain and transfer new knowledge from animations. Another way in which lecture videos reduce cognitive load is by segmenting, which is the chunking of information to allow learners to engage with small pieces of new information and give them control over the flow of the information. Segmented videos divided into small pieces can be searched and viewed according to the 94 Sörensen and Canelas; Online Approaches to Chemical Education ACS Symposium Series; American Chemical Society: Washington, DC, 2017.


needs of the student (34). Segmenting can be accomplished by making short videos or including “click forward” pauses within a video where students are provided with a question and then prompted to respond to a still screen by inputting an answer or clicking forward to continue viewing. Both of these approaches have been shown to be important for student engagement with videos (9) and learning from video (34). He, Swenson and Lents examined the incorporation of video tutorials as a supplement to learning in an undergraduate analytical chemistry course (14). These authors concluded that online video tutorials are “a valuable, flexible, and cost-effective tool for improving student mastery of chemistry problem solving” (14). Brecht et al. examined the feasilibility and effectiveness of lecture videos as a form of supplemental instruction in an accounting course. This study suggested that video lectures allow students to be more actively involved in the learning process, which can increase their level of interest and achievement (35). By increasing student motivation and engagement, cognitive understanding will improve and thus result in conceptual learning gains (36, 37). These expectations are supported by Mayer’s cognitive theory of multimedia learning (38). In another study, a series of 59 problem-based lecture videos covering different areas in a first year undergraduate calculus course were developed and posted to the course website for the students to use (39). The researchers collected self-reported data using a survey and open-ended response questions and found that students perceived the videos as useful, easy to follow, and effective in helping them understand new material (39). Although there are studies that show students generally have a positive perception of lecture videos (30), there is also evidence suggesting a subpopulation of students who strongly dislikes them. Harley et al. and Jensen found that even though students liked having lecture videos available as a supplemental resource, they preferred traditional-format, live-lecture courses (40, 41). One possible explanation is that students may be resistant to the use of lecture videos as a replacement for live lectures because it requires them to do work at home. As a result, some students may come unprepared to participate in the in-class, active learning part of the course. Instructors try to avoid this issue by holding students accountable for reviewing the required material prior to coming to class. This can be accomplished by assigning homework or implementing a pre-class quiz on information that can easily be obtained from the lecture videos (8). Despite the noted advantages, there are some challenges associated with the implementation and effective use of lecture videos (see Tables 1 and 2). The effects of lecture videos on academic performance are mixed. While some researchers have observed that lecture videos help students achieve better test scores (12, 42, 43), other studies showed no significant impact from the use of these tools on the grades or examination performances (44–46). For example, after controlling for initial GPA differences and absences, Traphagan et al. found students with video lecture access did not differ on performance measures from student with no lecture video access (30). Advocates believe that lecture videos are as effective as in-person lectures at conveying basic information (34, 40). However, some—both instructors and students—believe that lecture videos cannot be considered a substitute for the face 95 Sörensen and Canelas; Online Approaches to Chemical Education ACS Symposium Series; American Chemical Society: Washington, DC, 2017.


to face classroom lecture, but only as an enrichment of and complement to it (17, 47). Some studies reported that students do miss being able to ask questions or get immediate clarification on concepts (48, 49). In addition, the tendency for college students to mind-wander while watching videotaped lectures constitutes a barrier to learning of content (50, 51). There is evidence that some instructors worry that lecture videos will have a negative impact on students’ willingness to attend class. In this case, instructors express concern that the availability of video lectures will diminish the importance of the traditional lecture and significantly alter the university experience of the students (3). With respect to quantification of lecture attendance, there are confounding findings. One study suggests that lecture videos have little to no influence on attendance of in-class lectures. Only 10%-15% of students were found likely to miss lecture because they perceive lecture videos as a complete substitute for class attendance (23). However, Traphagan et al. found that “students with lecture video access attended class less frequently than students without access to them and students who viewed lecture videos more frequently had more absences (30).” The authors also noted that the availability of additional course materials online, such as PowerPoint slides and lecture notes, had a greater negative impact on classroom attendance than lecture videos (30).

Table 1. Key Student Benefits and Challenges of Lecture Videos Benefits

• Catch up on missed lectures (26) • Allow control over learning and reduce anxiety (29) • Reduce cognitive load (32, 33)

Challenges

• Perception of lecture videos as more work to do outside of the classroom (8) • Not being able to ask questions while watching the video lectures (48)

Table 2. Key Instructor Benefits and Challenges of Lecture Videos Benefits

• Classroom time can be used more effectively and creatively (19) • Promotes thinking inside and outside the classroom (27)

Challenges

• Creating lecture videos: technology and time demands (8) • Availabilty of lecture videos reduces student attendance (30) • Students new to method may be initially resistant (48)

96 Sörensen and Canelas; Online Approaches to Chemical Education ACS Symposium Series; American Chemical Society: Washington, DC, 2017.


Conclusions and Future Directions Recent advances in web-based lecture capture technology have catalyzed change and unlocked entirely new directions for lecture video use. A survey of the literature reveals that lecture videos have both benefits and disadvantages associated with them. While there are limitations, lecture videos appear to have potential as a useful learning resource. In terms of learning and performance, various studies found lectures videos to have either a positive, negative, or similar impact in comparison to traditional lectures. One explanation for these conflicting findings could be that the varying results depend on differences in the quality of the videos themselves or differences in the contexts of these studies. Thus, research-based knowledge about teaching and learning with lectures videos—both in general and in chemistry, specifically—is still in its infancy, and further research and longitudinal studies are needed to understand the effectiveness of lecture videos and students’ experiences with them.

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