The WWW-based Presentations as a Complementary Part of Conventional Lectures in the Basics of Informatics: Is It Worth It? Pekka Makkonen University of Jyväskylä Department of Computer Science and Information Systems P.O. Box 35, Fin-40350 Jyväskylä, Finland Tel: +358-14-603090 Fax: +358-14-603011 E-mail: pmakkone@jyu.fi Abstract Hypertext and the WWW appear to affect learning positively enabling the constructivist learning environment to support a student’s knowledge construction and a more active student role. However, the problems associated with them may endanger the benefit on learning. Thus, the role and the forms of hypertext and the WWW must be discussed. Because of the common problems of "information overload" and "lost-in hyperspace" we suggest guided tours in the form of a slideshow presentation as a solution to organize a hypermedia presentation on the WWW for learning the basics of informatics. These slides include links to the appropriate supporting web sites. In addition to the idea of a guided tour, based on cognitive flexibility theory, we also suggest that the use of search engines and directories must be promoted. This paper describes the use of guided tours as a complementary part of conventional lectures in the learning of the basics in informatics. We claim that learning can be promoted in the spirit of constructivism, situated action and cognitive flexibility organizing a course work based on guided tours as well as search engines and directories. We analyze the benefit of an optional course work including the use of guided tours and in addition the use of search engines and directories on the WWW. We assess the learning outcomes of the students comparing the students who have completed the optional course work to the students who have not participated in the optional course work. Learning outcomes were significantly better in the group of students who completed the optional course work. The results confirm both the theoretical discussions presented in this paper and our previous results. 1. INTRODUCTION During the 90s the reform work of teaching has reached universities. For example, Isaacs [10] and Rosenthal [20] have reported several problems in regard to traditional lecture based teaching. These problems include ineffectiveness, promoting passivity and isolation in students. In the context of technology and related sciences, some revisions have been suggested to improve lecturing as a teaching method by activating students using e. g. cooperative learning in small groups and essay-writing assignments about technical topics [10]. From this perspective lecturing has its possibilities by correcting previously mentioned problems, but also other learning methods must be considered. In informatics a course work utilizing information technology and its new possibilities may be a good and natural alternative for conventional lectures. Hypertext reflects a human's way of thinking and provides an opportunity to process information and interrelatedness between information cues [13]. Since hypertext and hypermedia enable an alternative view for learning supporting knowledge construction and individual learning, it can be an alternative for conventional lectures or textbooks. Thus, hypertext and hypermedia provide an ideal environment for learning based on a constructivist approach. One alternative for the conventional lectures is a hypermedia presentation on the World Wide Web (WWW). Hypertext and hypermedia do not typically offer an explicit mechanism to help learners better interpret and assimilate information, the context surrounding its creation and use, or the perspectives on the information of the author or other learners [25]. Simply improving information access without supporting learning leads directly to the problems of "information overload" and "lost-in hyperspace". Thus, students need some degree of guidance as well as the form and structure of hypermedia presentations must be discussed. In this paper we introduce our approach to use the WWW to overcome previously mentioned problems and to take advantage of the features of the WWW as a complementary part of conventional lectures. The WWW provides both the possibility to organize information in a strict form (e. g. using trails and guided tours) and also opportunities for free “surfing” with its advantages and disadvantages. To realize the benefits of the WWW we suggest the solution of three layers. These layers are (a) the support of guided tours as a slide show on the WWW, (b) the support of appropriate links, and (c) the support of search engines and directories. We analyze the power of our approach based on comparing the learning outcomes of the students who participated in our optional course work to the outcomes of those who did not participate in the optional course work. The paper is organized as follows: In section two we describe the character of learning of the basic concepts from the perspective of psychology. Section three describes constructivism as a view of learning. In section four we discuss the opportunities of the WWW in learning. The fifth section presents our experiment and results. In section six we draw conclusions based on our results. 2. NATURE OF LEARNING CONCEPTS Our study recognizes hypertext as a knowledge construction tool and learning as knowledge construction. Thus, we understand learning especially from the perspective of the constructivist theory (constructivism). According to constructivism, an individual learns new concepts in relation to his/her prior knowledge [19] (for more details about constructivism, see section 3). The psychological perspective of our research can be divided into the perspective based on cognitive psychology and the perspective based on developmental psychology. In this section we introduce these perspectives. They both emphasize that learning is knowledge construction, which makes them suitable for our research. 2.1. Perspective of Cognitive Psychology From the perspective of cognitive psychology we distinguish declarative and procedural forms of knowledge. Declarative knowledge represents cognizance or awareness of some object, event, or idea [22]. Declarative knowledge of ideas is often characterized as schemas [21], which are ideational constructs that are defined by attributes that they inherit from other schemas. Procedural knowledge describes how learners use or apply their declarative knowledge. Ryle [22] describes this type of knowledge as knowing how. An intermediate type of knowledge is structural knowledge, which mediates the translation of declarative into procedural knowledge and facilitates the application of procedural knowledge. According to Diekhoff [9], structural knowledge is the knowledge of how concepts within a domain (e.g. in informatics) are interrelated. It describes how declarative knowledge is interconnected. The basics of informatics include two kinds of learning. First, students learn to understand the field of informatics and its basic concepts. Second, students learn to use computers and utilize instructions to facilitate the use of computers. These two goals emphasize the learning of both declarative and procedural forms of knowledge. Since both forms of knowledge are important, we argue that the structural form of knowledge is important. Structural knowledge enables learners to form the connections that they need to use scripts or complex schemas [12]. It is typical for the basics in informatics that the basic concepts form structures. For example in our basic course on informatics the themes (for more details about the contents of the course, see subsection 5.1) form structural knowledge. Thus, we comprehend learning as a knowledge construction process of both declarative and structural knowledge. In this process a learner's goal is to approach an expert's knowledge structure which is the same as the requirements of a course. 2.2. Perspective of Developmental Psychology From the perspective of developmental psychology conceptual knowledge can be approached using Collis's [7] modification of Piaget's stages of development. This approach creates a basis for evaluating learning outcomes emphasizing the quality of learning concerning a single concept and interrelatedness between the concepts. Based on Piaget's stages of development a SOLO (Structure of the Observed Learning Outcome) taxonomy has been developed which divides learning outcomes into five classes. These classes reflect the quality and the awareness of a learning outcome. Learning outcomes (i.e., definitions of concepts) can be classified as follows using the SOLO taxonomy [3]: - Prestructural. - Unistructural. - Multistructural. - Relational. - Extended Abstract. A student's response can be classified according to the capacity, relating operation, and consistency and closure of his/her response. Pre-structural responses are based on irrelevant or inappropriate data (level 1). Unistructural responses are based on conclusions on one aspect (level 2). Multistructural responses are based on isolated relevant data (level 3). Relational responses are based on relevant data and an understanding of the interrelations of different data in responses (level 4). Extended abstract responses are based on an understanding of data and interrelations both in the context of a question and in unexpected situations (level 5). 3. CONSTRUCTIVISM AS A VIEW OF LEARNING In this section we introduce constructivism as a view of learning especially from the perspective of the use of the WWW. Widely known and discussed views associated with (computer supported) learning are behaviorism and its opposite constructivism. Behaviorism is interested in a student’s behavior (reactions) in relation to teaching (stimulus), while constructivism is interested in the mental processes which affect the behavior of a student [19]. A traditional lecture is mainly based on the behaviorist approach while course works and projects are typical constructivist learning. Constructivism asserts that learners construct knowledge by making sense of experiences in terms of what is already known [4]. In constructivist learning the concept of a mental model is essential. Learning is comprehended as the development of a learner’s mental models (or declarative and structural knowledge). Constructivism is an essential basis when applying the WWW for teaching and learning [4]. While the goal of constructivism is to recognize and help to facilitate a learner’s ability to construct knowledge when applied to teaching information retrieval on the Internet, it also provides the teacher with a structure for teaching. By focusing on concepts and connecting them to mental models, instructors and teachers can gain both confidence and control over the amount of material they cover in the small blocks of time usually allotted to teaching and training. Integrated with experiences that learners use to alter and strengthen mental models, the constructivist approach to teaching information retrieval also gives users a needed structure to get the most out of the Internet. Despite the promise of constructivism several researchers emphasize the meaning of guidance. For example, Silverman [24] points out that providing the right amount of traditional instruction, students seem to favor constructivist environments. He suggests different tools to support constructivist lessons. 4. THE WWW IN LEARNING Vast information resources are available to teachers and students via the WWW. However, the problems inherent in any information system such as disorientation, navigation inefficiency and cognitive overload are multiplied on the Internet [4]. However, these problems can be overcome using a suitable pedagogical approach and/or appropriate tools. Constructivism that mentioned in section three is the basic approach for the Internet solutions in learning. Additionally, it is useful to discuss the use of the WWW from other perspectives. In this section we introduce trails and guided tours as a way to improve the usefulness of the WWW. In addition, we introduce the concepts of situated action and cognitive flexibility, since these concepts are useful while applying the WWW for learning. One way to organize a presentation on the WWW is trails and guided tours. Trails connect a chain of links through information spaces [2]. These can include multiple “recommended” trails through a network. Guided tours restrict users to the trail prohibiting detours. While trails lower cognitive overhead (or overload) by recommending the next logical link to take, guided tours reduce overhead further by removing all other choices. Thus, they can also prevent the phenomenon of lost-in hyperspace. The term situated action emphasizes the interrelationship between an action and its context of performance [6]. The success of a computer supported learning environment depends not just on the software, but on the context in which that software is used [5, 14]. Situated action emphasizes a person's responsiveness to the environment and focuses on the improvisory nature of human activity [18]. Situated action theory emphasizes the local management of activity as mediated by relevant environmental cues [1, 24]. The implications for learning are that appropriate actions are generated from a recognition of appropriate opportunities given by the context. In addition to situated action theory, Jacobson et al. [11] emphasize also the meaning of cognitive flexibility theory affecting hypertext based learning. This theory proposes that complex knowledge may be better learned for flexible application in new contexts by employing case-based learning environments that include features such as: (a) use of multiple knowledge representations, (b) link abstract concepts in cases to depict knowledge-in-use, (c) demonstrate the conceptual interconnectedness or web-like nature of complex knowledge, (d) emphasize knowledge assembly rather than reproductive memory, (e) introduce both conceptual complexity and domain complexity early, and (f) promote active student learning. Based on above it is important to comprehend the views of learning while outlining courses as well as comprehending ways to use the WWW in learning. We stress three issues. First, we must discuss what the right amount of traditional (behaviorist) teaching is. Second, we must analyze what the right way to use the WWW is. Active learning must be promoted and the pitfalls of the WWW must be avoided. Third, scaffolding support is needed to support constructivist learning. 5. METHODS We pursued a study concerning a WWW-based course work based on the idea of trails and guided tours supported by the use of search engines and directories. In this section we describe our experiment, sample, measures and tests, followed by the results of our study. 5.1. Experiment At the University of Jyväskylä the themes of a course introduction to automatic data processing are introduction (including the themes Meaning of Automatic Data Processing, Information Society and Problems Utilizing Computers), presentation of data in the PC environment, computer software, hardware technology, data communications, and the meaning of information technology in business. The course usually lasts 10 weeks including lectures (8 hours), compulsory practical exercises (18 hours) in basic skills with personal computers and the Internet as well as the final examination. The course of spring 1998 lasted the same amount of time including the previously mentioned activities and in addition material and activities on the WWW to support the lectures in the constructivist fashion. Our approach to use the WWW for teaching and learning was combining - idea of trails and guided tours on the WWW, - both behaviorist teaching/learning and constructivist learning, - situated action, and - cognitive flexibility theory. In the WWW-based learning the basic point is situated action. The constructivist approach is the commonly accepted principle for learning. As mentioned in section two the structural form of knowledge is typical for informatics, it is natural to approach the learning and teaching of it from the perspective of constructivism. However, in our context students need guidance at the beginning of learning. Thus, the traditional learning methods in the behaviorist manner must be accepted as a part of teaching and learning methods. We introduced our approach for the students and administered the pre-questionnaire at the beginning of the course. The results of it [15] support our approach. Over 58% of the students considered both the lectures and printed lecture notes and the material on the WWW significant or strongly significant (based on a 5-point Likert scale ranging from strongly insignificant to strongly significant). Additionally, below 9% of the students considered both the lectures and printed lecture notes and the material on the WWW insignificant and none of them strongly insignificant. We organized our lectures realizing the previously mentioned approach. Thus, the lectures consisted of - printed lecture notes, which all students got at the beginning of the course, - conventional lectures, - lecture notes on the WWW including the links to the supporting sites, and - optional course work in regard to lecture notes on the WWW. Because of our context, we claim that conventional lecture and printed lecture notes are needed as a behaviorist part of a course, but lecture notes on the WWW provide an opportunity to the constructivist approach. The lecture notes on the WWW were organized in the form of a slide show using Microsoft Powerpoint 97 and its Internet assistant. These tools enable that the slides in each lecture can be organized in the strict form of a guided tour on the WWW supporting a student who is at the beginning of learning in informatics and not familiar with computers and the WWW. Each slide of a slide show can include a set of links to interesting WWW sites and in this manner a slide show can also be comprehended as a trail. Our slides included the links concerning the critical concepts to the appropriate link pages, which were evaluated to support the learning of these concepts best. The selection of the links on the slides was based on the list of critical concepts to learn produced by the group of the teachers (n=12) of informatics in our university. Since the slides are on the WWW, a student can also support her/his learning using search engines and directories. Thus, the form of a lecture is flexible and it can be seen as a trail or a guided tour depending on the situation and information needs. This enables different views and brings a real constructivist way of learning, since the role of instructional media shifts from one which seeks to maximize the communication of fixed content and/or skills to one in which students engage themselves in the knowledge construction process. In this sense our approach is also consistent with cognitive flexibility theory. To realize the benefit of the lecture notes on the WWW we organized a course work in which students were expected to enter their findings in their personal diaries. These findings included their opinion about (a) the general form of presentation, (b) the links provided by the teacher, and (c) the links found by the students themselves using search engines and directories. Additionally, the students were expected to give various examples about what they have learned during the course work. To promote the students’ participation in the optional course work, the students got credits by completing the course work for the final examination. Although course work is a constructivistic part of the course, the teacher’s office hours were available as an additional resource to promote their work. The students had six and a half weeks for the course work before the final examination. The work was expected to be realized as a personal work or in groups of two or three students. 5.3. Sample One hundred and three students, 78 females and 26 males, whose mean age was 23 years (range 19-42 years), entered the course and completed both pre- and post-treatments. All students were familiar with university lecturing. They familiarized themselves with the use of a WWW browser and basic search engines and directories (i. e., Altavista and Yahoo) before the introduction of the optional course work. All students studied informatics as a minor and were required to participate in the practices concerning the use of personal computers and the Internet (18 hours) and they all had the same exercises concerning these matters. Participating in the lectures (8 hours) and the course work was optional. Forty-six of them, 38 females and 8 males, whose mean age was 22 years (range 19-40 years), participated in the optional course work. 17 of them completed the course work individually, 23 in the groups of two students and 6 in the groups of three students. The students used 13 hours (range 5-30 hours) for the course work on an average. They attended 6.5 hours in the lectures and used 43 hours for the whole course on an average. Fifty-seven students, 39 females and 18 males, whose mean age was 23 years (range 19-42 years) did not complete the optional course work. These students attended 4.9 hours in the lectures and used 31 hours for the whole course on an average. 1.1.1 5.4. Measures and Tests We utilized a SOLO taxonomy based measure to clarify learning outcomes and their quality (see subsection 2.2). Both the pre-treatment and the post-treatment contained 15 separately selected items. These items were chosen randomly from 88 critical concepts to learn of the whole learning area. 88 critical concepts were selected by the group of the teachers (n=12) of informatics in our university. In each test respondents produced 15 definitions of randomly selected basic concepts. The responses of the students were ranked from 1 to 5 based on the quality of learning. The basis for the rankings was the contemporary definitions of these concepts that were included in the material on the WWW. In the responses the students were expected to define concepts using certain sentences clarifying the basic properties of each concept and connections between these properties. Additionally, based on the SOLO taxonomy the students were also expected to express alternative definitions for the concepts and the meaning of a concept in a larger sense, if they noticed it necessary. The pre-treatment was administered at the beginning of the first lecture. Since our intention was to study the effect of the WWW as a complementary part of conventional lectures and lecture notes, the post-treatment was administered as the first part of the final examination. Both in the pre- and post-treatments the students had as much time as needed to produce their responses. 1.1.2 5.5. Results We compared learning supported by the WWW (the experimental group) and learning without the support provided by the WWW (the control group). The dependent variable was the quality of learning (based on a SOLO taxonomy based measure). Since the data based on the responses of the students disagreed with the normal distribution, the Mann-Whitney test as a non-parametric test was appropriate for this experiment. The pre-treatment Mann-Whitney test showed a significant difference between the experimental group and the control group (p=.018). The mean for the experimental group was 1.59 and the mean for the control group was 1.67. Cronbach's alpha to show the reliability in the pre-treatment was 0.72. The post-treatment Mann-Whitney test showed that the difference between the experimental group and the control group was significant (p<.001). The mean of the experimental group was 2.62 and the mean of the control group was 2.46. Cronbach's alpha to show the reliability in the post-treatment was 0.77. The learning outcomes of the students who had completed the optional course work were better compared to the students who had not completed the optional course work based on the WWW. The students who participated in the course work were in worse situation at the beginning of the course, but after the course and the course work the learning outcomes were significantly better in the experimental group. The results can partly be caused by the lower attendance of the control group in our lectures (difference is 1.6 hours between the experimental group and the control group). However, since the students in the experimental group used 13 hours for the course work on an average and these students used the WWW 10 hours more than the students in the control group, we argue that the WWW-based course work had the greatest influence on learning. 1.2 6. DISCUSSION The results of this paper support the use of guided tours in the form of a slide show. The finding confirms both Bieber’s and his colleagues’ [2] discussion concerning the benefit of guided tours and trails and the results of pre-questionnaire where we found that the students have a positive attitude to the idea of the WWW as a medium to present lectures [15]. Our preliminary analysis of the students’ course works [16] also supports the results of this paper. We found that especially the form of a slide show, links and appropriate link pages are beneficial in learning. Search engines and directories are less effective in learning than guided tours in the form of slide shows or links and link pages (destinations) [16]. However, we claim that search engines and directories may be more effective after the basic course in informatics when students are more familiar with these tools. In learning in the constructivist manner computers and their applications can be comprehended as cognitive tools, in other words, tools for knowledge construction. According to Mayes [17], these tools are more effective in the hands of an experienced user. A qualitative analysis of the course work answers is needed. In the course work students were required to give reasons for their ratings and analyzing this information will clarify what the reasons for the success or the failure are. The results of this paper provide more evidence to promote the use of the WWW for the learning of basic concepts especially in the context of informatics. Our results in this and the previous papers support both the constructivist learning and the use of guided tours supported by the links. Brandt [4] points out that teaching and learning based on constructivism must concentrate on concepts and connecting them to mental models. The WWW-based guided tours provide these concepts in a strict and controlled form and links provide connections to a student’s mental models. Thus, the course work of three layers provides a real basis for constructivist learning as a complementary part of conventional lectures. However, more evaluation from the perspective of constructivism may be needed. Motivation is important to evaluate, since in constructivist learning it is important that students are actively engaged in learning and knowledge construction [8, 12]. Additionally, as mentioned in section four cognitive flexibility theory stresses the meaning of activity. Thus, the evaluation of motivation is also meaningful from this point of view. Our results are consistent with situated action theory and cognitive flexibility theory. From the perspective of situated action theory our previous paper [16] showed that the basics of informatics is the right context for guided tours supported by appropriate links preventing the pitfalls in the use of the WWW (“information overload” and “lost-in-hyperspace”). This paper confirms these results. 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