Impact of problem-based learning to students and teachersh

When I came into 9B class every time, I have often heard that physics is one of the most difficult subjects to understand and they couldn’t apply it to the everyday life. That was a problem, and PBL begins with a problem, or a scenario, presented in the same context, as it would be encountered in real life (Woods, 1994; Savery, 2009). As this was a PBL approach, the main purpose was for students to identify their learning needs, and then proceed to investigate these needs through subsequent research (Peterson & Treagust, 1997; Savery, 2009).

I wanted my student to solve this problem and I asked them “If you were a science teacher how could you motivate primary or secondary schools’ students to become more interested in science topics?” Following this, students were divided into groups of 5 or 6 and work together throughout the process, design, implement, and report their projects. Before the students embarked on their projects, I briefed them on the aims and objectives of the project. They defined the problem, and produced hypotheses, then discussed them and eliminated false hypotheses, thus forming a true hypothesis toward a solution of the problem. After they wanted help from some other science teachers, their parents and enlisted their helps (e.g., teaching ideas, suggest experiments, and help to provide books and develop materials), they came to the next process prepared, studied and learned the necessary concepts required to solve the problem. In the light of their friends’ comments, they researched some science experiments that were just for fun, some were "tricks," and some would allow students to obtain useful scientific concept and also applied a number of additional criteria: low cost, simplicity of design, feasibility, safety, compactness, less time to set up.

The aim of all students in PBL process was to provide their friends with some science experiments that a child of any age can perform to help demonstrate principles of physics. The teaching materials prepared by the students included their overall plan for teaching the subject in classroom, and the activities and resources that would form the basis of this teaching. They knew that that transferring knowledge from an instructor to a passive learner will never success . Thus it has become inevitable for the learner to take an active role in and shoulder the greatest part of the responsibility in teaching learning activity.

To be realized the aims of the new physics curriculum, in this study, students placed at the center of the activity so that the whole activities proceeded under their control, based on their specific needs and preferences. Since the learner neither can nor does to be loaded with all sorts of knowledge available, they should determine the limits of the knowledge they needed. They decided on the learning objectives and also on the way to access those objectives. They corrected and improved their learnings through practicing the mechanism of self-appraisal. In other words, the study tried students to get actively take part in learning activities and eventually become a life-longer learner. My role was as an instructor in this activity confining to act as an efficient facilitator rather than a knowledge-conveyor.

The process had taken about a month up, and an agreement upon the solution of the problem was reached. I evaluated them on the basis of their participation and effort in solving the problem in the PBL process. During this time, I provided feedback, asked guiding questions, and encouraged them to share and discuss their ideas. In carrying out their project work, the students went through five consecutive phases (Chin and Chia, 2006): (1) identifying the problem to be investigated, (2) exploring the problem space, (3) carrying out the scientific inquiry, (4) putting the information together, and (5) presenting the findings, teacher evaluation, and self-reflection. The following models developed in PBL lessons to explain a real-world phenomenon, which can also be considered a physics subject.

Table 1. A sample process of PBL teaching design for incandescent bulb model

Phase	Teacher	Group 1
The Problem	Imagine that you are a physics teacher. You always hear “we don’t like physics and we don’t understand it”. What will you do? in your class. Can you teach some physics that you and your students like	We familiarized ourselves with some issues related to “electric” by discussing and reading books, asking our parents on topics such as electric current, Edison’s life, differences between bulb (incandescent light) and fluorescent lamps. We then decided to make “electric bulb” that we wanted to investigate.
Learning Objectives	What do you know about electric? What do you need to know? How can you find out what you need to know?	We tried to find various possible sources of data and information. For example, We did some laboratory experiments and interviews with our parents and science teachers. Our two friends researched included books, articles, videos, website links.
Resources	You should use our laboratory and library, You want help from other science teachers or your parents	We collected data to answer how would teach electric. We decided to make “a model of bulb”. We used the science laboratory to carry out our investigations. One of our father was electric engineer. He helped us.
Product Specifications	Can you describe your process by giving examples of the sequence of activities that you used to implement your study?	We made our own electric bulb (model) and get a bright, though brief, glow. We used two nails, a short length of thin iron wire, a bottle, a cork to fit the bottle, and cell batteries with a length of covered copper wire. My father helped us for idea and making this lamb. We sticked the two nails through the cork and we attached the iron wire to the nail points. After that, we fitted the cork into the neck of the bottle, allowing the nail heads to remain outside and the iron wire to go inside. With the covered wire, we connected the dry cells to the heads of the nails, as shown in the illustration Figure 1 . Electric bulb model
Presentation	How did you produce light? What is resistant? What do you know about electric current?	Although we used iron wire in our model, the real incandescent light bulb contains tungsten wire called a filament. This wire has a very high resistance to electricity. When electric current flows through it, it produces heat. In our bulb model, When the iron wire becomes hot, it combines with the oxygen and burns up. To prevent this, all of the air is removed from the light bulb and is replaced with an inert gas such as argon.

Table 2. A sample process of PBL teaching design for simple crane model

Phase	Teacher	Group 2
The Problem	Imagine that you are a physics teacher. You always hear “we don’t like physics and we don’t understand it”. What will you do? in your class. Can you teach some physics that you and your students like	We discussed ourselves with some issues related to “Pascal's Principle” by reading books, asking our parents and teachers on topics such as Pascal, Pressure, Force, Physics of Fluids and Hydraulic Engineering. We then decided to make “simple crane model” that we want to investigate.
Learning Objectives	What do you know about energy? What do you need to know? How can you find out what you need to know?	We knew about energy a little. We tried to find various possible sources of data and information about energy. For example, by doing laboratory experiments and interviews with our teachers and parents. We investigated related books, articles, videos, website links
Resources	You should use our laboratory and library, want help from other science teachers or your parents when you want	We collected data from web to answer how would teach “Pascal's Principle”. We saw a simple Crane model in www.arvindguptatoys.com. We used the science laboratory to carry out our investigations. We made a simple crane by taking professional support from an carpenter.
Product Specifications	Can you describe your process by giving examples of the sequence of activities that you used to implement your study?	We used several old plastic syringes, old plastic drip tubes, pieces of wood, screws and ordinary hand tools from carpenter. The movements of this crane are based on the principle of hydraulics. It can be understood by filling two plastic syringes with water and attaching them with a plastic drip tube. When you push the plunger of the first syringe, the plunger of the second syringe will move out. Thus the motion is transmitted through water pressure from the first to the second syringe. The motion of the second plunger is transformed into the swivel, or up-down movement of the crane. Figure 2 . A simple Crane model
Presentation	How did you do it? Why did you use water? What do you know about pressure?	Pascal's principle states that a pressure applied to an enclosed liquid is transmitted everywhere in the liquid. Hence, if a pressure is applied to one side of an enclosed liquid, all the other walls containing the liquid feel the same pressure. The pressure is transmitted without being diminished. For Pascal's principle to be useful to hydraulics, the fluid should be an incompressible liquid, which will transmit the applied pressure without changing its volume.

As a result of the process, “science teams” that were called “science circus” were occurred spontaneously. At the end of the first semester, students present their experiment for not only students but also their teachers to participate in their exhibits in and to introduce cutaways and working models to encourage the students and their teachers to learn about how things work rather than what they look like. After finishing implementing activity, students and teachers were asked to give some written feedback on the “science circus” project.