Students’ Perceptions of Impact of Scaffolds in Problem-Based Learning

The purpose of this study was to investigate whether students perceive certain types of scaffolds to have higher impact on their daily learning. The participants (N = 229) for this study are enrolled in an institution that uses problem-based learning (PBL) as the instruction method. The students’ perceptions of the 16 types of scaffolds utilised in the curriculum were consolidated using a Scaffold Impact Questionnaire that was devised. Besides rating the level of impact of the scaffolds on their learning, the participants were also asked to provide written comments to state why they found the scaffolds useful or not useful. Confirmatory factor analysis using SPSS AMOSTM was also conducted to obtain a statistically validated model categorising three groups of scaffolds – hard, semisoft and soft scaffolds. The data obtained was then analyzed by 1 Authors: Choo, S. S. Y, Yew, E. H. J. & Schmidt, H. G. Students’ Perceptions of Impact of Scaffolds in Problem-Based Learning 36 | P a g e means of analyses of variance. Results of the study indicated in general that soft scaffolds (e.g. facilitator, team and class contributions), semi-soft scaffolds (e.g. worksheets) were perceived to have higher statistically significant impact on learning compared to hard scaffolds (e.g. textbooks). However, there are also certain hard scaffolds such as practice questions and computer animations that are deemed by students to keep them actively engaged in the learning process, thereby seen as having an impact. These findings suggest that scaffolds, especially soft scaffolds, do play a significant role in enhancing students’ learning within the social constructivist framework of PBL. Furthermore, the importance of the role of facilitator and collaborative small group learning which are key features of PBL is again reinforced based on the outcome of this study. Students’ Perceptions of Impact of Scaffolds in Problem-Based Learning 37 | P a g e Introduction Problem-based learning (PBL) is an instructional approach aimed at helping students develop flexible understanding and lifelong learning skills (Hmelo-Silver, 2004; Schmidt, et al., 2007; Simons & Klein, 2007). In the process of learning, students develop the abilities to collect information, analyze data, construct hypotheses, and apply deductive reasoning to a problem at hand (Barrows & Tamblyn, 1980; Schmidt, 1993). The PBL tutorial process can be characterized as follows. First, students working in small collaborative groups are given a problem consisting of a scenario or a case study that requires analysis and an explanation. After initial discussion and brainstorming of learning issues, the students proceed to carry out some self-study before returning to their groups for further discussion and elaboration based on the knowledge acquired and proposes alternative justifications for the presented problem (Norman & Schmidt, 1992). Throughout these discussion sessions, the student groups are guided by a tutor, who models good Students’ Perceptions of Impact of Scaffolds in Problem-Based Learning 38 | P a g e strategies for learning and thinking (Greening, 1998; Hmelo-Silver, 2004; Schmidt, et al., 2009). PBL is associated with social constructivism, whereby students construct knowledge through interactions (Greening, 1998; Savey & Duffy, 1996). In the context of social constructivism, the distance between what an individual can do with or without assistance or support is known as the zone of proximal development (ZPD) (Roehler & Cantlon, 1997; Vygotsky, 1978). Providing assistance in this ZPD is known as scaffolding. In order to qualify as scaffolding, the learning or teaching event should allow students to be able to eventually carry out and complete a task that they would not have been able to manage on their own (Verenikina, 2008). In PBL, the main instructional materials used in the curriculum are usually the problems, which should be carefully designed to be relevant and interesting for the students (Khoo, 2003; Schmidt, et al., 2009). Good problems should be complex enough to promote thinking as well as motivate the students’ need to learn (HmeloSilver, 2004). Besides the problems, advocates of PBL do not forbid Students’ Perceptions of Impact of Scaffolds in Problem-Based Learning 39 | P a g e structured educational activities and guidance where appropriate (Ertmer & Simons, 2006; Saye & Brush, 2002; Simons & Klein, 2007; Taylor & Miflin, 2008). These additional sources of support include references, audiovisual aids and even lectures relevant to the problem. In fact, most medical schools that have been implementing PBL include lectures and laboratory sessions as scaffolding tools to support student learning (Hamdy, 2008). However, despite the common use of scaffolding tools in PBL, there have been differing opinions regarding the role of instructional guidance during PBL (Hmelo-Silver, Duncan, & Chinn, 2007; Kirschner, Sweller, & Clark, 2006; Schmidt, et al., 2007). Kirschner et al. (2006) suggest that PBL is a minimally guided approach and is less effective than instructional approaches that place a strong emphasis on direct instruction. In contrast, there are others who assumed that PBL does provide extensive scaffolding and guidance to facilitate meaningful learning for students (Hmelo-Silver, et al., 2007; Schmidt, et al., 2007; Simons & Klein, 2007). Moreover the use of scaffolds to enhance inquiry and students’ learning achievements was Students’ Perceptions of Impact of Scaffolds in Problem-Based Learning 40 | P a g e demonstrated by a study conducted by Simons and Klein (2007). The study examined the impact of scaffolding and student achievement levels in a PBL environment, whereby students were subjected to different scaffolding conditions. Results from this study revealed that students who were given access to scaffolds performed significantly better in the post-tests, compared to the group with no scaffolds provided (Simons & Klein, 2007). Since the tasks provided in the PBL curriculum may be complex to novice learners, scaffolds that structure these tasks will benefit both students as well as tutors. Besides reducing complexity of the tasks, scaffolds also augment the ability of the students in completing the required tasks independently (Clark & Graves, 2005; Ertmer & Simons, 2006). Furthermore, previous studies suggest that the verbal presentation of PBL problems may not necessarily provide sufficient information to prepare students to recognize visual or non-verbal cues that could be important in certain subject areas (Hoffman & Ritchie, 1997; Hung, 2011). In a recent study investigating the impact of scaffolds on student learning as perceived by students, it was found that out of Students’ Perceptions of Impact of Scaffolds in Problem-Based Learning 41 | P a g e the various types of learning supports provided in a PBL environment, students generally viewed tutor interventions as the most important scaffold for their learning (Choo, et al., 2011). Thus there is a need for flexible scaffolds within the PBL curriculum that could be used to adapt to the problem-at-hand, and to support the learning needs of students. However, there is no systematic overview of the types of possible scaffolds for social-constructivist learning environments like PBL. In addition, not much information about their actual or perceived effectiveness was studied in detail. Thus the objective of this study was to find out whether students perceive certain types of scaffolds to have higher impact on their daily learning process. With sufficient knowledge in this aspect, it would be easier for curriculum drafters to provide materials that could effectively and efficiently support the learning needs of students. The results reported in this article provide a first contribution to clarifying these issues. First however, some important theoretical distinctions need to be discussed. Students’ Perceptions of Impact of Scaffolds in Problem-Based Learning 42 | P a g e Scaffolds Till date, there are two types of scaffolds that have been distinguished in the literature, in a general context pertaining to scaffolding. These two scaffold types are referred to as hard and soft scaffolds. As defined by Saye and Brush (2002), hard scaffolds are basically static supports that are generally developed before a task is assigned. Such scaffolds may be provided once a task is assigned to the learner. Hard scaffolds may be in the form of online or paperbased cognitive tools such as reference books or readings which functions to provide hints or descriptions of the concepts that students should learn about in the process of understanding the problem (Saye and Brush, 2002). With reference to the description of hard scaffolds, it is likely that scaffolds of the above-mentioned nature may be of use to student learning under a PBL environment. In view that PBL do require students to be self-directed learners, hard scaffolds such as textbooks, provided article readings or practice questions pertaining to the topic at hand, may impact the students’ understanding in a positive manner. Students may refer to Students’ Perceptions of Impact of Scaffolds in Problem-Based Learning 43 | P a g e such scaffolds while they are working on the learning tasks, and use them throughout the problem-solving process. Some studies have suggested that fading of hard scaffolds is possible and should be encouraged once the students have gained ability in performing the assigned tasks (Belland, Glazewski, & Richardson, 2008; Puntambekar & Hubscher, 2005). With increasing expertise, fewer resources should be provided to the students. In this way, independent learning is encouraged while providing a form of flexible scaffolding (Schmidt, et al., 2007). On the other hand, “soft” scaffolds refer to the actions of the teacher or tutor in response to the learner’s efforts when the learner indicates a specific need (Saye & Brush, 2002). Instances of such scaffolds in PBL would be tutor interventions based on student questions or peer responses within the small group. Soft scaffolds emerge when there are momentary needs. If these needs do not emerge, the scaffold need not be administered. Since one of the characteristics of PBL involves small-group learning whereby the students collaborate to think and generate possible solutions for the Students’ Perceptions of Impact of Scaffolds in Problem-Based Learning 44 | P a g e problem or task, brain-storming sessions of the solutions could be instances of ‘soft scaffolds’. As various institutions may employ various types of scaffolds in the curriculum to aid in student learning, scaffolds could be categorised differently into more distinct groups apart from ‘hard’ and ‘soft’. As defined earlier, soft scaffolds emerge when there are momentary needs and within the PBL curriculum, there may be other types of scaffolds consisting of ‘soft scaffold’ elements, which could be developed or provided to enhance student learning. For example, students may utilise materials of hard scaffold nature such as worksheets or internet resources related to the subject matter either during self-directed learning or group discussions. Tutors may also use such scaffolds during their facilitation of the teams or class to check or affirm students’ understanding of the subject matter. In the instance of a worksheet, the tutor could utilise some of the questions to guide the student’s metacognitive processes, in the event that the student expresses particular concerns or demonstrates difficulties understanding certain concepts in relation to the lesson curriculum. Students’ Perceptions of Impact of Scaffolds in Problem-Based Learning 45 | P a g e Similarly, internet resources or computer animations summarising information on concepts that could be relevant to the topic of interest may also serve as support tools in the tutor’s explanations to the students. Therefore, the mode of how these types of scaffolds are administered in PBL could vary from that of a conventional non-PBL environment. To further distinguish between scaffolds of the abovementioned nature, such examples of materials or scaffolding events may be referred to as ‘semi-soft’ scaffolds. Thus it can be seen that various types of scaffolds could be deemed useful and even necessary in different situations in the PBL educational context. However, as there may be different forms of scaffolds provided for students in PBL, it would be useful if the value of each scaffold type is examined. In addition, there is a lack of studies providing an overview of the different types of hard and soft scaffolds. Therefore, one first step would be to find out the students’ perspectives on which scaffolds they consider effective in contributing to their learning. This is because students are in the best position to assess the various scaffolds and their adequacy to support Students’ Perceptions of Impact of Scaffolds in Problem-Based Learning 46 | P a g e learning. Considering that they are exposed to problem-based learning throughout their course of study, it will be appropriate to use them as informants for this study. To that end, we administered a questionnaire to a cohort of 229 students who are enrolled in a tertiary institution that uses PBL as the learning pedagogy. The students were asked to rate and comment on the impact that different scaffolds have on their learning. The data obtained was then analysed. Using the obtained data, the first research question for the study aimed to firstly test the three-category theory of the scaffolds of this study which involves hard, semi-soft and soft scaffolds, which has not been carried out in any known studies till date. Validation of the scaffold categorization was then performed and analysed accordingly. The second research question aimed to unravel more insights to what extent the various types of scaffolds are perceived by students to have a different level of impact on their learning. Methods Participants Students’ Perceptions of Impact of Scaffolds in Problem-Based Learning 47 | P a g e The sample consisted of 229 participants enrolled in courses at a polytechnic in Singapore, specifically in the respective areas of Biomedical Sciences, Biotechnology, Materials Science, Pharmaceutical Sciences and Environmental Science. The breakdown of the participants in terms of their years of study and frequencies of gender is shown in Table 1. Out of the total number students who were eligible for inclusion in this study (n=823), 28% of the students chose to participate. Table 1 Gender and age range of participants in respective year of study Year of study Total number of participants (n) Gender Age Male Female Mean S.D. Year One 95 43 52 16.54 0.97 Year Two 71 24 47 17.44 1.07 Year Three 63 31 32 18.73 1.30 Students’ Perceptions of Impact of Scaffolds in Problem-Based Learning 48 | P a g e Educational Context In this particular institution, the instructional method is PBL for most of the courses it offers. In this approach, five students work together in one team under the guidance of a tutor or facilitator. Each class comprises four to five teams. A unique feature of the PBL approach used in this institution is that students work on one problem during the course of the day (Alwis & O'Grady, 2002). A typical day starts with the presentation of a problem. Next, students discuss in their teams, come up with tentative explanations for the problem, and formulate their own learning goals (Hmelo-Silver, 2004; Schmidt, 1983, 1993). During this process, students are provided with a template (referred to as Problem Definition Template), which they utilize to organize and scaffold the points brought up during team discussion. This Problem Definition Template (PDT) basically consists of three columns for students to fill in what they know, do not know, and need to find out in order to solve the problem. The facilitator would then go through the PDT together with the students through discussions as a class. This is to allow the facilitator to guide Students’ Perceptions of Impact of Scaffolds in Problem-Based Learning 49 | P a g e or prompt the students’ thinking towards understanding the learning objectives for the lesson. Subsequently, periods of self-study follow in which students individually and collaboratively try to find information to address the learning goals. At the end of the day, each team will come together to present, elaborate upon, and synthesize their findings. During the team presentations, there will be a series of class discussions generated by questions raised from either the students or facilitator, which encourage collaborative learning. By the end of the lesson, the facilitator will then provide a closure to the lesson by means of a concise presentation summarising the learning points generated throughout the day and relating them to the topic’s objectives. Apart from the problem statement, there are other forms of learning supports (e.g. worksheets) provided for the students to utilise throughout the lesson and scaffold the learning process. Resources are also provided for students to access and enhance their knowledge before (e.g. recommended textbooks, preand postlesson readings) and after (e.g. extracurricular talks, practice Students’ Perceptions of Impact of Scaffolds in Problem-Based Learning 50 | P a g e questions) lesson time. Examples of these scaffolds will be shared in further detail later in the next section. Categorization of scaffolds Although as mentioned earlier, scaffolds in general can be considered as either hard or soft, in this context of PBL, there are also scaffolds that can be regarded as a combination of both. For instance, due to the collaborative learning environment that students work in throughout the day, students tend to discuss and complete a worksheet together with their teammates, thus making the worksheet a form of flexible scaffolding instead of a hard scaffold. As mentioned in the Introduction section, the worksheet may also be a tool that facilitators utilize in different ways based on the learning needs of students during discussion time with the team or class. Likewise, the PDT is also used by the tutor to guide the students’ cognitive processes by allowing them to organise their thoughts or inputs via team and class discussions. Hence, in this study, we aim to recognise the distinctiveness of such instances of learning supports which we classify as ‘semi-soft’ scaffolds (refer to Educational Context Students’ Perceptions of Impact of Scaffolds in Problem-Based Learning 51 | P a g e for more details). Table 2 below shows the list of the scaffolds used in the particular curriculum after classification into three categories of scaffolds – hard, soft and semi-soft. Table 2 Categorization of types of scaffolds used in PBL Type of scaffold or scaffolding event Category of scaffold Pre-lesson readings Hard scaffolds Recommended textbooks Extra-curricular talks or workshops related to the subject Post-lesson readings Practice questions provided after lesson Contributions of the facilitator (i.e. tutor) Soft scaffolds Team contributions (involvement of a small group of 5 students with the learning of the individual) Class contributions (involvement of a larger group of about 25 students) Team presentations Students’ Perceptions of Impact of Scaffolds in Problem-Based Learning 52 | P a g e Worksheets Semi-soft scaffolds Hands on activities (e.g. demonstrations or practical activities in class) Presentation by facilitator at the end of the lesson Computer animations or videos Internet resources Additional resources (e.g. text documents) embedded in worksheets Problem Definition Template Instrument Scaffold Impact Questionnaire. A Scaffold Impact Questionnaire was devised and administered to the participants to investigate what students perceive as important scaffolds that have an impact on their learning in a PBL environment. Students were asked to rate the level of impact different scaffolds have on their learning. They were also asked to provide written comments to justify the ratings for each item (i.e. scaffold). The list of 16 items that were measured for this study is shown in Table 1. This list was based on the types of learning supports that are utilized in the polytechnic. Students’ Perceptions of Impact of Scaffolds in Problem-Based Learning 53 | P a g e Each item in the questionnaire was rated on a 5-point Likert scale: 0 (not at all), 1 (a little), 2 (moderate), 3 (much), and 4 (very