Teaching floating and sinking concepts with different methods and techniques based on the 5E instructional model

Students’ alternative conceptions in science and technology are often resistant to change, at least through traditional instruction (Fisher, 1985; Raghavan, Sartoris & Glaser, 1998; Tytler, 1998; Önen, 2005; Hardy, Jonen, Möller & Stern, 2006; Saka, 2006). Some teaching methods and techniques like conceptual change texts (CCT), concept cartoons (CC), prediction-observation-explanation (POE), interviews about instances and events, interviews about concepts, drawings, fortune lines, relational diagrams, computer assisted materials, word association and analogies are used to provide meaningful learning and conceptual change (White & Gunstone, 1992; Stephenson & Warwick, 2002; Atasoy, 2004; Besson & Viennot, 2004; Çepni, Taş & Köse, 2006; Keleş & Çepni, 2006; Hovardas & Korfiatis, 2006; Çepni et al., 2007). In recent years, researchers have started to use different techniques together to overcome the well known alternative conceptions (Grotzer, 2003; Kawasaki, Rupert Herrenkohl & Yeary, 2004; Zhang, Chen, Sun & Reid, 2004; Besson & Viennot, 2004; She, 2005; Havu-Nuutinen, 2005; Uzuntiryaki & Geban, 2005; Yenilmez & Tekkaya, 2006; Yürük, 2007; Cardak, Dikmenli & Saritas, 2008; Cardak & Dikmenli, 2008; İpek & Çalık, 2008; Kurnaz & Çalık, 2008; Taştan, Dikmenli, & Çardak, 2008; Türk & Çalık, 2008; Ürey & Çalık, 2008; Özmen, Demircioğlu & Demircioğlu, 2009). In the related literature, researchers mainly use CCT and support it with other teaching methods and techniques to overcome the alternative conceptions on the grounds that using some other supportive activities with CCT is more effective than traditional CCT (Çetingül & Geban, 2005; Özmen et al., 2009). These approaches have already served as the basis of many studies in establishing their conceptual framework. For example, Yenilmez and Tekkaya (2006) investigated the effectiveness of combining CCT and discussion web strategies on students’ understanding of photosynthesis and respiration in plants; and Uzuntiryaki and Geban (2005) investigated the effect of CCT together with concept mapping instruction and traditional instruction on 8th grade students’ understanding of solution concepts. Yürük (2007), tried to compare the effectiveness of an instruction supplemented with CCT over traditional instruction on students’ understanding of galvanic and electrolytic cell concepts. İpek and Çalık (2008), used different conceptual methods (work sheet, analogy, CCT) within the four-step constructivist teaching model to eliminate students misconceptions about electric circuits, how “electric charge flows in series and parallel circuits” and “how the brightness of bulbs and the resistance changes in series and parallel circuits.” Ürey and Çalık (2008) displayed a sample teaching of the cell and its organelles by combining different conceptual change methods within the 5E instructional model. Türk and Çalık (2008) presented a sample teaching activity about endothermic-exothermic reactions for teacher usage by using different conceptual change methods embedded within the 5E instructional model. Kurnaz and Çalık (2008) used different conceptual change methods embedded within the 5E instructional model to teach heat and temperature and express the difference between them. Taştan et al. (2008) investigated the effects of concept maps, together with CCT, given to 11th grade students on the subject of molecules carrying genetic information. Özmen et al. (2009) aims to determine the effects of CCT accompanied with computer animations on 11th grade students’ understanding and alternative conceptions related to chemical bonding.

Studies about floating and sinking

One of the topics, of which many studies were conducted to provide conceptual change, is floating and sinking. In studies about floating and sinking, students’ alternative conceptions were discused and different activities were organized to remove these conceptions. Yin, Tomita and Shavelson (2008) determined students’ alternative conceptions about buoyancy and density subjects with diagnostic items at the beginning of the unit. Then, they prepared worksheets by taking the alternative conceptions into consideration and applied them to students. When students still had problems, they prepared POE activities to overcome students’ misconceptions. Gürdal and Macaroğlu (1997) tried to make out how students perceive the concepts of floating and sinking, and benefited from experimental activities in teaching these concepts. Reid, Zhang and Chen (2003) looked into the performance effect of simulation based on scientific discovery learning with experimental and interpretative support on determining intuitional understanding, adaptation to situation and combining knowledge of students. Zhang et al. (2004) made a three-phased (interpretative support, experimental support, reflective support) experimental study to support simulation-based scientific discovery learning. They examined the effect of simulation-based scientific discovery learning on meaningful and scientific learning, and reflective thinking about the subject of floating and sinking. Kawasaki et al. (2004) used a experimental method to examine theories that students built up and modelled about the floating and sinking unit in 3rd and 4th grades. Kang, Scharmann, Noh and Koh (2005) prepared animations on computers to show that size and weight would not be criteria for floating and sinking of an object. At the beginning of the research, students were given a text requiring explanations to get acquainted with their prior knowledge. Then, another text, including a dilemma situation, was applied to students. Eventually, animations were applied to students to evaluate the two situations. At the end of the study the researchers wanted students to write their beliefs about the subjects floating and sinking. Havu-Nuutinen (2005) examined effect of social argument and instructional process on conceptual change about floating and sinking concepts and benefitted from worksheets to examine conceptual change. Hardy et al. (2006) compared two different programs with the support of various instructional equipment in constructivist learning environments about the topics of floating and sinking. They examined the effects of instructional support within constructivist learning environments for elementary school students’ understanding of floating and sinking. McGregor and Gunter (2006) prepared an in-service course for elementary school science teachers about floating and sinking concepts. They benefited from experimental activities prepared from foods and a Titanic simulation related to these foods.

When studies on CCT supported by other teaching methods and techniques to overcome the altenative conceptions are examined, it can be seen that there were not any studies on floating, and sinking concepts using different teaching methods and techniques. Analogies are mostly used with CCT (İpek & Çalık, 2008; Türk & Çalık, 2008; Ürey & Çalık, 2008; Kurnaz & Çalık, 2008). Concept maps (Uzuntiryaki & Geban, 2005; Taştan et al., 2008), discussion web strategies (Yenilmez & Tekkaya, 2006), computer animations (Sahin, Calik & Cepni, 2009; Özmen et al., 2009) and worksheets (İpek & Çalık, 2008; Türk & Çalık, 2008; Ürey & Çalık, 2008; Kurnaz & Çalık, 2008; Yin et al., 2008) are also prefered teaching methods and techniques used together with CCT. According to the related literature, using only one conceptual change method in teaching may bore students in the lessons. Using different teaching methods and techniques together with the 5E instructional model can be effective to provide conceptual change (Jacobson & Kozma, 2000 in cited Özmen et al., 2009; İpek & Çalık, 2008; Türk & Çalık, 2008; Ürey & Çalık, 2008; Kurnaz & Çalık, 2008; Yin et al., 2008; Özmen et al., 2009). When studies concerning floating and sinking concepts were examined, it is seen that worksheets (Havu-Nuutinen, 2005; Yin et al., 2008), simulations (Reid et al., 2003; Zhang et al., 2004; McGregor & Gunter, 2006), animations (Kang et al., 2005), experimental activities (Gürdal & Macaroğlu, 1997) and constructivist learning environments (Hardy et al., 2006), POE (Yin et al., 2008) are used separately. We prepared teaching material about floating and sinking based on the 5E instructional model with some supporting teaching methods and techniques like CCT, CC, worksheets, animation and POE. CCT used in this study was different from the ones found in the literature because at the beginning of CCT, scientific ideas were adopted into daily life situations, activities were presented as short texts with concept cartoons, and the text is supported with hands on activities and animations. Table I shows a literature summary of students’ alternative conceptions concerning floating and sinking concepts (Rowell & Dawson, 1977; Strauss, Globerson & Mintz, 1983; Parker & Heywood, 2000; Macaroğlu Akgül & Şentürk, 2001; Reid et al., 2003; Zhang et al., 2004; Kang et al., 2005; Ünal & Coştu, 2005; Havu-Nuutinen, 2005; Özsevgeç & Çepni, 2006; Gearhart et al., 2006; Moore & Harrison, 2007; Joung, 2009).

Table I. Alternative conceptions about floating and sinking concepts

Alternative conceptions	Researchers
Small and light objects floats, heavy objects sink	Rowell & Dawson, 1977; Strauss et al., 1983; Kang et al., 2005.
Size of buoyancy force depends on volume and shape of the objects or just depends on the mass of the objects	Reid et al., 2003; Zhang et al., 2004.
Objects heavier than water sink	Özsevgeç & Çepni, 2006.
More gravity is applied to heavier objects	Özsevgeç & Çepni, 2006.
Sinking of objects is related to their weight	Macaroğlu et al., 2001.
Sinking and floating is explained with objects shape, surface area, air containing, density, being weight and raw material	Parker & Heywood, 2000.
Hanging objects are accepted the same as sinking objects	Ünal & Coştu, 2005.
Floating or sinking of objects are just explained with only volume or weigh of the objects or volume of the liquids
Density of the floating objects is higher than that of sinking and/or hanging objects
Density of hanging objects is lower than that of liquids
Buoyancy force effect on hanging object is more than weight of ebullient water.
Density of hanging object is equal to that of floating object
Objects with geometric shape floats, others sink
When we make a hole in an object, it sinks
Volume of the liquid effects buoyancy force of the sinking volume of objects. If the liquid is less, buoyancy force will have more effect on it (on the object?)
When objects part keep afloat increased, buoyancy force also increases
Floating and sinking concepts are explained with physical characteristics like heavy, light, big, small	Havu- Nuutinen, 2005.
Objects float because of the air in their structure	Moore & Harrison, 2007.
Objects float because it is made of floating object
God floats the objects
Boat wants to float so it floats
Floating is just depends on the shape of objects	Gearhart et al., 2006.
When some part of an object is outside the water or river, it floats. And when all parts of an object is inside the water or a river, it sinks	Joung, 2009.

The theoretical framework of the study

In Turkey, the Science and Technology Education Program that is in accordance with constructivist approach was developed in 2004. Students' textbooks, workbooks and teachers' guidebooks were prepared according to the 5E instructional model. The definition of stages in the 5E instructional model, teaching methods and techniques used to support 5E instructional model are presented below.

5E instructional model

This model consists of five phases. Relevant literature describes the implementation of each phase of the 5E instructional model in teaching science concepts (Çepni, Akdeniz & Keser, 2000; Krantz, 2004; Wilder & Shuttleworth, 2005; Çalık, 2006; Özsevgeç, 2006; Saka, 2006; Özsevgeç, 2007; Orgill, & Thomas, 2007; Vincent, Cassel & Milligan, 2008; Er Nas, 2008) as:

1. Engagement: It includes drawing students’ interest to the concept, revealing students’ prior knowledge about the concept, making students aware of their own knowledge and querying their own knowledge about the concept. At this stage, students are not expected to express the correct concept. This stage is a warm up phase in which students become ready to learn.

2. Exploration: This is the most active phase for the students. Students try out their own knowledge, doing observations and gaining experiences about the concept. They freely work in groups. They try to explore scientific knowledge. Teachers' direct students to study in video, computer and library environments, and students are encouraged to solve problems.

3. Explanation: This is the most active phase for the teacher and includes students sharing and debating their own experiences with each other. Students are encouraged to compare their prior knowledge with observations and explain the relationship between the two. At this stage, teachers could benefit from such methods as computer software, flash animations, CCT, discussion, expression and video.

4. Elaboration: Students are encouraged to adapt the new knowledge they have acquired to different situations and to associate it into their daily life. Work sheets, model preparation and activities, including drawing and problem situations, complete the learning needs related to daily life to increase thinking skills. Questions are used to enhance the relationship between the concept and daily life. Moreover, at this stage students find answers to questions that are asked in order to motivate them at the “enter stage.”

5. Evaluation: Students query new knowledge of concepts they have learned during the previous four stages and make an extraction. And, eventually, they assess their own improvement.

Teaching Methods and Techniques used to support 5E instructional model

Prediction- observation- explanation

The prediction-observation-explanation (POE) method is used in laboratory experiments to focus on students’ concept learning and to facilitate presentation and order of the issue. Laboratory activities carried out by POE give students a chance to apply what they have already learned and allow generalizations of their own scientific knowledge to science subjects outside of the curriculum. The POE technique is used to deepen the understanding of the concept (White & Gunstone, 1992). Students are asked the originations of the events to motivate them to consider, and an opportunity is given to them to make observations. As a result of the predictions and observations made, students are asked to give explanations about the concept. In this context, the main underlying cause of students’ thinking about the concept can be revealed (White & Gunstone, 1992; Köseoğlu, Tümay & Kavak, 2002).

Worksheet

Worksheets can be used for different purposes such as development of scientific process skills with laboratory activities (Havu-Nuutinen, 2005; Moore & Harrison, 2007; Yin et al., 2008; İpek & Çalık, 2008; Türk & Çalık, 2008; Kurnaz & Çalık, 2008; Şahin et al., 2009; Karslı & Şahin, 2009). Before the preparation of worksheets, their structure should be explicit. Situations such as pictures, images, cartoons, and current and interesting questions can be used to make worksheets interesting and eye-catching.

Conceptual Change Texts

A CCT is a text used to put the challenges between scientifically correct concepts and alternative concepts clearly and is used to support classroom activities and facilitate students learning (Chambers & Andre, 1997; Uzuntiryaki & Geban, 2005; Çaycı, 2007). What is intended with CCT is to correct students’ prior knowledge or organize students’ new knowledge. It is prepared to provide students to think that their existing knowledge is insufficient for explaining a new situation (Sevim, 2007). CCT started with a situation about common alternative conceptions. Students are asked to predict what will happen at the situation. Questions are used to activate students’ alternative conceptions. Then general alternative conceptions are stated and the wrong parts of these alternative conceptions are explained. Students question their alternative conceptions and figure out lacking points in their knowledge. Dissatisfaction of students about their existing knowledge is expected. New and scientifically correct knowledge of the concept about the topic is presented with examples. Finally, teachers discuss the situations with the students to help them understand the scientific explanations (Chambers & Andre, 1997; Uzuntiryaki & Geban, 2005; Pınarbaşı, Canpolat, Bayrakçeken & Geban, 2006; Çaycı, 2007; Sevim, 2007).

Concept Cartoon

The concept cartoon (CC) is a teaching method used frequently in courses. Alternative concepts in science are as short texts with cartoon characters (Keogh, Naylor & Downing, 2003). CC are prepared as a poster and defined as an instructional material to support instruction (Kabapınar, 2005). Although a CC seems very simple, it has a complex structure. Scientific ideas are adapted into daily life situations with the help of CC. Trying to present every scientific situation that appears in daily life with a story is very difficult and takes more time. But this way, students have opportunities to compare their scientific knowledge with daily life situations (Keogh & Naylor, 1999a). Every cartoon should present different ideas for every situation (Keogh & Naylor, 1999a; Stephenson & Warwick, 2002; Clark, 2005). Text should have very small space in concept cartoons. Spaces should be left in speaking bubbles of concept cartoons to give opportunity to students to evaluate themselves (Keogh & Naylor, 1999a). CC could be prepared as homework for students (Keogh & Naylor, 1999a). It could also be prepared as worksheet (Kabapınar, 2005). Complex and abstract science concepts could be expressed simply by cartoons (Stephenson & Warwick, 2002; URL-1, 2005). Discussion about CC should be made on probable situations instead of theories (Keogh & Naylor, 1999b; Clark, 2005; Kabapınar, 2005), and should include general alternative conceptions and scientifically right ideas (Kabapınar, 2005; Clark, 2005). It is recommended that giving names to the cartoons and providing students to say their ideas with using cartoons names, so that students can explain their ideas more comfortably.

Animations

Animation is described as the motion of many pictures and figures in a scenario. It offers various opportunities to the educational environment. It facilitates understanding, and helps complex natural events be understood more clearly (Taş, 2006). It also gives an opportunity to students to see natural events that could not be taken into a classroom environment (Ayas, Yılmaz & Tekin, 2001). It gives an opportunity to do dangerous experiments in a computer environment confidently in a short amount time, to repeat the experiments (Sinclair, Renshaw & Taylor, 2004; Yılmaz & Saka, 2005), and give an opportunity to students to observe experiments virtually in the schools that do not have equipment required for the experiments (Yılmaz & Saka, 2005). It encourages students to be motivated and active during course time and increases students’ interest towards science and technology (Yiğit & Akdeniz, 2003; Sinclair et al., 2004).

Purpose

The purpose of this study is to determine the influences of the prepared instructional material based on the 5E instructional model combined with CCT, CC, animations, worksheets and POE on conceptual changes about floating and sinking concepts.