The impact of project-based learning environments on conceptual understanding: The "Recycling" concept http://www.ied.edu.hk/apfslt/v17

Prior to the application, the vast majority of the students were observed to fail in providing a complete definition of the concept of recycling, and had instead defined recycling as the process of producing paper out of waste paper (see Figure 5). The drawings by the students and the results of the interviews point at a similar direction. Out of the 18 students who took part in the pre-test, 15 described the concept of recycling exclusively by drawing paper and a recycling bin (see Figure 6). In the pre interview, 5 of the students who took the interview defined the concept of recycling through a link of producing new paper out of collected waste paper. The statement "It refers to the collection of used paper, to produce new paper" provided by the student coded S5 supports this finding. The direct link the students harbor between the concept of recycling and the recycling of paper may be a result of the fact that the overwhelming majority of the recycling activities which take place around the students are about the recycling of paper. It is clear that the more responsibility the students are given in terms of the environment, the more responsive and responsible the students will be to the environment (Harness & Drossman, 2011). There are also projects supported by the Ministry of Education, albeit in limited numbers, on the recycling of valuable waste. One such project is the "Recycling Project for Books Provided Free of Charge" project implemented at schools (Çelik, 2011). The implementation of such projects at schools may have contributed to increasing the students' level of knowledge about the recycling of paper. Çimen and Yılmaz (2012) found, through their study aiming to assess the level of knowledge 6th, 7th, and 8th grade students in primary education have with respect to recycling, as well as their recycling behaviors, that the most frequently used recyclable product the students use is paper. The participation of the students in their daily routine, in activities aiming to ensure recycling of paper may have contributed to providing them a sufficient level of information on this aspect of the concept. This finding, in turn, suggests that applied learning which finds its way into behaviors produces more lasting results. In the pre-test, just 5 of the students provided drawings suggesting that not only paper but also bottles were recyclable materials. It is well known that recycling refers to the physical or chemical processing of solid waste, enabling the use of the materials as raw materials for a second time (Çimen & Yılmaz, 2012). Many solid waste materials other than paper and bottles can be recycled. The lack of representation of other types of solid waste in the students' drawings, as well as the lack of mention of such materials in the interviews may have something to do with the students lacking adequate knowledge about the matter. In a detailed study on the recycling of packaging waste as part of the primary education curriculum, Çelik (2011) found that the curriculum did not provide adequate information, and the students had only limited knowledge about the matter. This leads to the hypothesis that even though various projects for the recycling of paper take place at schools, to be witnessed by 4th grade students, the curriculum fails to provide sufficient knowledge, and lacks applied projects regarding the utilization of different types of solid waste. In a similar vein, in the pre-test some of the students exhibited confusion of the concept of recycling and the recycling bin itself. The statement provided by student S14 in the pre-test "It is the box where used paper and batteries are disposed of" and the drawing provided by student S9 (see Figure 7) support this argument. The confusion the students have between the concept of recycling and the recycling bin itself may be due to the lack of sufficient emphasis on the concept of recycling as part of the curricula. Pike, Shannon, Lawrimore, Mcgee, Taylor & Lamoreaux (2003) conducted a case study with some students at the Francis Marion University related to recycling. At the end of the study; it was found that when students were trained related to recycling boxes and recycling, students living in campus apartments had significantly reduced the waste stream. Also it was found that the project based learning environment had a positive effect to teach sustainability to the students. It is clear that the education given to schools on the concept of recycling will positively affect not only the students but also the households in student houses. Maddox, Doran, Williams & Kus (2011) conducted a study to summarize and evaluate how school-level waste education promotes action at the household level. The project was conducted with 6705 elementary school children in 39 schools. Working together with the students in the research, the message of "Reduce, Reuse and Recycle" was taken to their families and sustainable waste management practices were provided. The results of the study showed domestic recycling behaviors will be positively affected by intergenerational influences with school-based waste education model. In this case, the recycling of waste should be given more place in the program, and students should contribute to their learning by carrying out projects that require active participation in the process.

While S2 student was in the preliminary interview unrelated description category, the final interview responded to the complete understanding category. Likewise, S2 coded student responded to the conceptual understanding test in the preliminary test, and the final test in the complete understanding category. In the last drawing, it is seen that the student puts the recycled paper only in the front drawing, but the recycled paper shows the material which can be recycled in addition to paper (Figure 7). The activities carried out through the project led to a new state of affairs whereby 15 of the students (See Figure 5) were able to associate recycling with waste materials, and provide accurate definitions. In the project-based learning environment the class was divided into 4 groups, each composed of 4 to 5 students working together towards the development of their own projects regarding the concept of recycling. In the initial stage to come up with the project, the students visited the school's material storage room with their teacher and decided on what they could do in terms of recycling. The students did some research on the issue first, to obtain in-depth knowledge about the concept of recycling. Making use of the waste materials available at the school's material storage room, the students designed new products and completed their projects. The projects carried out by the students aimed to provide them with information on what could be done in terms of the recycling of materials other than paper. Such new insights, in turn, found their way to the final interviews and drawings. A glance at the drawings provided by the students after the application of the project reveals that 7 out of 18 students drew a number of distinct types of solid waste together (see Figure 6). Furthermore, 2 students were found to refer to their projects in their drawings. For instance, student S3 took part in the "a new armchair" project along with her group mates. The drawing by the student described how they produced a new armchair out of an old one which had been out of use, by drawing the armchair before and after the project (see Figure 3). The conclusion is that the projects where students work actively through direct participation in their learning environments had a positive effect on their conceptual development levels (see Table III) Indeed, numerous studies note that projects serve useful purposes in terms of establishing links between the knowledge learned in the classes and used in daily life (Blumenfeld et al., 1991; Bransford, Brown & Cocking, 2000), developing a creative classroom environment for the students (Shearer & Quinn, 1996), rendering learning an enjoyable process through actually doing and experiencing (Winn, 1997) and contributing to in-depth learning of concepts (Solomon, 2003).