Publications

In this chapter the role of teachers in teaching mathematization is discussed. As a basis a model for the pedagogical content knowledge, specifically adapted for the role of mathematics in physics, was developed and validated with an interview study with experienced physics teachers. Different foci of teachers with respect to their teaching strategies are being identified.

Problem-solving plays a central role among the various manifestations of the interrelations between physics and mathematics in the high-school physics classroom. Research on the problem-solving habits of physics high-school students shows that they often start and end solving problems by looking for seemingly relevant formulas, thus decrementing the development of their physics understanding. From another perspective, teachers were found to employ in their teaching different phys-math patterns which share in common one aspect: they all begin from physics (qualitatively) before moving on to mathematics. Here we describe a study on the use of a classroom activity (“Starting with Physics”) that attempts to motivate students to employ, when solving problems, physics concepts and principles before using formulas and other mathematical manipulations technically. Students receive only the first part of a problem consisting of a textual description of a phenomenon and the relevant mathematical information, without any subsequent questions. They are asked to describe and explain the phenomenon by using physics concepts and principles without using equations. A study was carried out in physics high-school classes that used this activity. The findings indicate that most of the students managed to adequately describe the events using appropriate physics concepts and principles and that the mathematics that they utilized helped them promote their physics understanding. The students were cognizant of the rationale of the activity’s design and its important contribution to their learning. This activity is highly appreciated by physics teachers. They claim that it emphasizes the common underlying physical principles of apparently different problems and supports problem-solving in physics. However, it is necessary to carry it out with the same students several times in order to bring about its habitual use.

We studied the learning of high-school physics teacher-leaders in a national Professional Learning Communities (PLCs) program that operates using a "Fan Model": the teacher-leaders' PLC is led by a team from the Weizmann Institute of Science, while they simultaneously lead regional PLCs of physics teachers all over Israel. The learning sequence of one learner-centered activity was chosen as the context for this study. We developed a theoretical framework: Physics Knowledge for Teaching and Leading (PKTL), which we used for a micro-level discourse analysis, together with the Knowledge Integration (KI) perspective. The results show that the evidence-based learning of a new learner-centered activity fostered the learning of physics and a rich array of other aspects of teacher-leaders' knowledge. The teacher-leaders' PLC turned out to be a meaningful, supportive, and enriching learning environment. We suggest that our program can serve as an effective model for the professional development of both teacher-leaders and teachers in regional PLCs.

The last decade has witnessed a strong increase in research that moves toward mutually beneficial collaboration between researchers and practitioners. This chapter focuses on such collaborations that aim to design resources for use in schools while also advancing theoretical understanding of the dynamics within such partnership. We refer to such endeavors as design-centric research-practice partnerships (DC-RPPs). To guide the development of productive DC-RPPs, we synthesize insights from three theoretical lenses: (1) scholarship of teaching and practitioner research, (2) change laboratory formative interventions, and (3) multilevel boundary crossing. These lenses, together with a framework that characterizes DC-RPPs based on the practical constructs of (1) processes, (2) roles, and (3) habits-of-mind, are used in a 3 × 3 theory-practice matrix to elicit and articulate nine design principles that can support productive DC-RPPs. We describe two cases that illustrate how the design principles come to life in authentic DC-RPPs (one with 3 middle schools, focusing on interdisciplinary learning, and the other with 22 high schools, focusing on physics) and conclude with a discussion of emerging work that could support DC-RPPs and recommendations for future research.

That mathematics is the "language of physics" implies that both areas are deeply interconnected, such that often no separation between "pure" mathematics and "pure" physics is possible. To clarify their interplay a technical and a structural role of mathematics can be distinguished. A thorough understanding of this twofold role in physics is also important for shaping physics education especially with respect to teaching the nature of physics. Herewith the teachers and their pedagogical content knowledge play an important role. Therefore we develop a model of PCK concerning the interplay of mathematics and physics in order to provide a theoretical frame for the views and teaching strategies of teachers. In an exploratory study four teachers from Germany and four teachers from Israel have been interviewed concerning their views and its transfer to teaching physics. Here we describe the results from Germany. Besides general views and knowledge held by all or nearly all teachers we also observe specific individual focus depending on the teachers' background and experiences. The results fit well into the derived model of PCK.

Teachers’ involvement in curriculum design is essential for sustaining the relevance of technology-enhanced learning materials. Customizing—making small adjustments to tailor given materials to particular situations and settings—is one design activity in which busy teachers can feasibly engage. Research indicates that customizations based in evidence from student work lead to improved learning outcomes. In this paper, we examine the customizations of four middle and high school teachers during their enactments of web-based inquiry science units. We examine how specific technology features afforded their customizations by providing tools for making adaptations and by making student work available as evidence for those adaptations. Cases built from classroom video and field note observations, interviews, and teachers’ curriculum artifacts, revealed three kinds of customizations: (a) devising timely instructional interventions to provide individualized guidance; (b) planning activities and adjusting milestones to align with students’ progress; (c) modifying existing materials to better integrate content into overall curriculum plans; and (d) incorporating scaffolds to better address students’ needs. We also identified three technology features that supported teachers’ customizations: (1) a system that logs student work for teachers’ inspection; (2) tools for conducting dynamic, formative assessment; and (3) an authoring environment that supports the re-design of units at multiple levels of granularity. We end by suggesting design principles for curriculum materials that support teachers’ customizations, as well as future directions for technology that would enhance teachers’ participation as designers.

Science curriculum development can involve changes in what is taught, to whom (target audiences), and how (ways of teaching and learning). This entry is concerned with the following questions: Why change the science curriculum? What should be changed? How and by whom is the change process initiated and sustained? The entry discusses various models for initiating and sustaining change.

Teaching the concept of Energy, a fundamental concept in any science education curricula, presents a great challenge. The observed difficulties may be attributed to the apparent vagueness regarding the meaning of energy, energy forms, energy transformation/conversion/transfer and energy conservation. A teaching approach, following Karplus (1981) idea of an operational definition of energy change and the first law of thermodynamics as relating energy change of a system to different mechanisms, was developed in order to address this challenge. We employed the concept of energy change as a unifying, measurable (through Joule-like experiments) and concrete property of different kinds of natural processes. “Energy language” was developed, together with teaching materials (activities, representations, demonstrations and experiments) which were administered to 7th grade students. This approach follows the ideas presented in the position paper that summarized the Girep 2010 workshop: Teaching about energy (Eylon & Lehavi, 2010).

The scaffolded knowledge integration framework translates our knowl­ edge integration perspective on learning into guidance for those de­ signing science instruction. Taken together, the scaffolded knowledge integration framework, the knowledge integration perspective on learn­ ing, and the cognitive processes offer three lenses for understanding science learning and instruction. These three lenses allow researchers to combine the results from a variety of research endeavors and will ulti­ mately, we hope, lead to a more robust understanding of learning in general and of science learning and instruction in particular.

Children learn in formal (school) and informal (out-of-school) contexts. Do these children integrate what they learn in these different contexts? While some research shows that they do most of the literature points to a serious lack of contact between these contexts when dealing with related content. During the last two decades, many education researchers have called to bridge this gap. The aim of this paper is to develop a model to guide dialogue and cooperation between staff members within formal and informal educational contexts, in order to foster this integration. We present: (1) a rationale for bridging between formal and informal learning contexts, including the need for a comprehensive and practical model to guide this effort; (2) a design-based research methodology for developing the model; and (3) the resulting 4 × 4-bridging model. We argue that this model can help educators, engaged in formal and informal learning, to develop practical and productive partnerships with each other.

This paper describes a teaching experiment designed to examine the learning (i.e., retention of content and conceptual development) that takes place when public scientific web lectures delivered by scientists are utilized to present advanced ideas in physics to students with a high school background in physics. The students watched an exemplary public physics web lecture that was followed by a collaborative generic activity session. The collaborative session involved a guided critical reconstruction of the main arguments in the lecture, and a processing of the key analogical explanations. Then the students watched another exemplary web lecture on a different topic. The participants (N=14) were divided into two groups differing only in the order in which the lectures were presented. The students' discussions during the activities show that they were able to reason and demonstrate conceptual progress, although the physics ideas in the lectures were far beyond their level in physics. The discussions during the collaborative session contributed significantly to the students' understanding. We illustrate this point through an analysis of one of these discussions between two students on an analogical explanation of the Aharonov-Bohm effect that was presented in one of the lectures. The results from the tests that were administered to the participants several times during the intervention further support this contention.

The Physics & Industry program is an elective, out-of-school, accredited program for high school physics majors, who meet on a bi-weekly basis for 15 months. The program currently into its 7th cycle, with over 150 graduates, implements a project-based learning instructional approach. Student pairs, coached by industrial engineers, design and construct a working model providing a solution to an authentic, open-ended technological problem, employing principles of electro-optics. The instructional design of the program enhances four learning dimensions as a way of supporting and scaffolding students’ efforts and guarding against the undermining effects of conflicting demands and natural attrition during the program: Learning to apply knowledge; Learning to use technological and cognitive tools; Learning to communicate; and Learning to become a member of a community. Our paper provides detailed examples of the activities employed in order to bring about the required knowledge enhancement and presents evidence of the effectiveness of the instructional design.

The present study was carried out in the context of a QM course for physics teachers participating in the Weizmann-Rothschild MSc program for excellent teachers. The physics courses in the program were especially designed for the teachers, and the interplay of mathematics and physics played a central role. The study investigated the goals of the course as conceived by the instructor, the intended plan for its implementation, the changes that were introduced along the semester in response to the feedback and the learning outcomes. The data-sources included observations, interviews, group discussion, oral and written feedback and a conceptual questionnaire based on the QMVI and the QMCS [1, 2]. The findings indicated that the instructor made a very clear distinction between the goals of this course and those of a graduate QM course for future scientists. The instructor reduced the level of mathematics and emphasized the conceptual ideas behind the mathematics ("developing sense of understanding"); he adapted a historical approach and elaborated on the logic behind the formulas. During the course both the instructor and the TA supported the teachers in mathematical aspects and responded dynamically to their needs by changing the assignments and the assessments. In spite of the reduced mathematical level, teachers' achievement in the conceptual questionnaire was similar to those of other groups reported in the literature. The teachers indicated that the course developed their confidence in coping with mathematical challenges and made them more aware of their students' needs.

Physics educators tend to consider public scientific lectures to be intellectual entertainment rather than a venue to teach/learn physics. This study presents empirical evidence showing that such lectures can be a useful instructional resource for students who lack the prior knowledge needed for formal learning of contemporary physics topics. Fourteen graduates of a preacademic physics course took part in the study. Two public web- lectures were used, one on quantum mechanics and one on astrophysics. The intervention included a collaborative phase after each lecture that dealt with the scientific argumentation and analogical reasoning presented in this lecture. The results show a significant increase in scientific content knowledge. This increase was independent of the lecture topic, with the watching phase and the collaborative learning phase contributing equally. The activities made a significant contribution to long term retention. The transcripts of the discussions reveal knowledge integration and seven dimensions of change in the declarative knowledge base. The activities also enhanced understanding of the nature of science (NOS) which was apparent, for instance, in a transfer of awareness of NOS features.

This article describes a teaching unit for Junior High School (JHS) students in Israel developed by a multidisciplinary team of experts from the fields of science teaching, medicine and dietetics. The unit aims to teach the main ideas of health and nutrition in a way that will arouse the students' curiosity and be relevant to them. To enhance learning, the team designed a virtual interactive learning environment which was implemented in a pilot study with several JHS schools.. This environment is based on data compiled by the Nutrition Department of the Israeli Ministry of Health, and includes nutrient values for more than 4,500 foods as well as the daily recommended nutrients and energy intake (DRI) for individuals. This interactive program can help users to create a personalized balanced menu and compare the user's consumption of nutrients with the recommended diet. The results of the comparison are depicted through various forms of knowledge representations such as text, histograms and charts, which cater to different teaching/learning/evaluating styles. The unit employs effective teaching methods such as authentic problem solving and communicating with others. The results of the pilot study suggest that through this technology-enhanced environment students can assimilate the main ideas of health and nutrition. Moreover, the findings show that students tend to share their acquired nutritional knowledge with their families thus acting as agents for change in this important area of knowledge.

Israeli junior high-school science teachers usually have a background in biology, and their knowledge of physics is limited. We show that by improving teachers' qualitative understanding it is possible to increase their confidence and willingness to teach physics. We conducted three-day workshops for teachers (n592), which were followed by ongoing activities and support. The teacher workshops were based on a new qualitative approach that we developed for studying mechanics, which has been shown to be effective with students. A study of teachers who had not participated in the workshop shows that they had the same conceptual difficulties as their students. A comparison of pre- and post-workshop questionnaires indicates that the participating teachers gained self-confidence in their ability to explain everyday phenomena, changed their views about the relevance and interest of physics to the students and were willing to implement the method in their classes.

Many large scientific projects and scientific centres incorporate some kind of outreach programme. Almost all of these outreach programmes include public scientific lectures delivered by practising scientists. In this article, we examine such lectures from the perspectives of: (i)lecturers (7) who are practising scientists acknowledged to be good public lecturers and (ii)audiences composed of high-school students (169) and high-school physics teachers (80) who attended these lectures. We identify and discuss the main goals as expressed by the lecturers and the audiences, and the correspondence between these goals. We also discuss how the lecturers' goals impact on the design of their lectures and examine how the lecture affects audiences with different attitudes towards (and interests in) physics. Our findings suggest that the goals of the participating lecturers and the expectations of their audiences were highly congruent. Both believe that a good public scientific lecture must successfully communicate state-of-the-art scientific knowledge to the public, while inspiring interest in and appreciation of science. Our findings also suggest that exemplary public scientific lectures incorporate content, structure and explanatory means that explicitly adhere to the lecturers' goals. We identify and list several design principles.

The present study examined continuity of learning between face-to-face and online environments in a "blended" professional development program designed for 16 physics teachers. The program had nine face-to-face meetings as well as continuous online exchanges between them through a website. The program focused on "knowledge integration" (KI) innovative activities in physics classes using an "evidence-based" approach: The teachers implemented the activities, collected and analyzed data about their practice and their students' learning, and reflected on the evidence with their peers. Five reflective tools were used to promote continuity: Your Comments, Hot Polls, Smashing Sentences, Hot Reports, and Mini Research. Continuity was assessed with regard to the ideas discussed by the teachers and the reasoning patterns that they employed. Analysis of the online exchanges in relation to teachers' face-to-face discourse revealed that the teachers discussed the same ideas (KI, evidence and learner-centered pedagogies), employed the same reasoning patterns (e.g., forming generalizations), and extended ideas in re-visitation. The online and face-to-face environments played different and complementary roles in the teachers' learning. This study shows that appropriate use of an online environment in a blended program can lead to a continuous course of learning and can transform a "9 once-a-month-meetings" workshop into a "9-month" workshop.

The focus of this collaborative research project of King's College London, and the Weizmann Institute, Israel is on investigating the ways in which teachers can demonstrate accomplished teaching in a specific domain of science and on the teacher learning that is generated through continuing professional development (CPD) programmes that lead towards such practice. The interest lies in what processes and inputs are required to help secondary-school science teachers develop expertise in a specific aspect of science teaching. It focuses on the design of the CPD programmes and examines the importance of an evidence-based approach through portfolio-construction in which professional dialogue paves the way for teacher learning. The set of papers highlights the need to set professional challenges while tailoring CPD to teachers' needs to create an environment in which teachers can advance and transform their practice. The cross-culture perspective adds to the richness of the development and enables the researchers to examine which aspects are fundamental to the design by considering similarities and differences between the domains.

We describe an evidence-based continuing professional development programme on knowledge integration (KI) for high-school physics teachers. Sixteen teachers participated in the year-long programme (about 40 face-to-face lessons and in-between computerised interactions). The teachers experienced the KI activities as learners and then engaged in an 'evidence-based' approach, i.e. implemented the activities in their classes, collected data about teaching and learning, analysed the data, and discussed the evidence collaboratively. The study investigated teachers' learning throughout the programme as reflected in the collective discourse held during the meetings by examining the ideas that were raised and how they were influenced by the evidence-based approach. The discourse reflects progress in teachers' tendencies and abilities to continuously find out about individual students' learning, and to adopt 'learner-centred' views. These views of teaching and learning related to the importance and legitimacy of students' learning from peers, the need to listen carefully to students' ideas and reflections, and the need to use a variety of methods for investigating students' learning in order to plan teaching. Importantly, teachers realised the need for the KI activities and their advantages. They were more willing to adapt them with required customisations. The evidence-based approach triggered two central reasoning patterns influencing teachers' learning: contrasting expectations with facts and making generalisations. Towards the end of the programme, the teachers realised the general importance of the evidence-based approach, beyond its support of the particular domain of KI, and they concluded that examination of their practice is a powerful tool for enhancing their teaching as well as their students' learning.

In this paper we describe a diagnostic study to investigate students' understanding of two basic formulae in physics. Based on the findings of the study, we have developed a classroom activity focused on the interpretation of formulae. The activity was developed cooperatively by physics education researchers and high-school physics teachers and was tried out in the teachers' classrooms. We describe the activity and present findings about students' attitudes towards the activity and the progress in students' understanding of three formulae.

For problem solving to serve as an effective learning opportunity, it should involve deliberate reflection, e.g., planning and evaluating the solver's progress toward a solution, as well as self-diagnosing former steps while elaborating on conceptual understanding. While expert problem solvers employ deliberate reflection, the novices (many introductory physics students) fail to take full advantage of problem solving as a learning opportunity. In this paper we will focus on self-diagnosis as an instructional strategy to engage students in reflective problem solving. In self-diagnosis tasks students are explicitly required to carry out self diagnosis activities after being given some feedback on the solution. In this and a companion paper, we will present research exploring the following questions: How well do students self-diagnose, if at all, their solutions? What are the learning outcomes of these activities? Can one improve the act of self-diagnosis and the resulting learning outcomes by scaffolding the activity?

Many teachers would agree that not all their A-level students appreciate the beauty of physics or enjoy solving complex problems. In this article, we describe a photo-contest activity aimed at narrowing the gap between physics and students. The photo contest, involving both students and teachers, is guided by the National Center of Physics Teachers in Israel. Students were requested to photograph a natural or contrived phenomenon, explain it using physical concepts and principles, present it to their classmates and finally submit the photographs to be judged by other students, teachers and a central committee consisting of experts, photographers and physicists. Seven teachers whose students were involved in the photo contest were interviewed. Teachers reported that, although only a few students presented their photos to the contest, many others were involved in various stages of the contest. The teachers were surprised to discover that the participating students were not necessarily the traditional high-achievers. All the teachers interviewed integrated the photographs into their regular physics lessons.

This article describes a new interdisciplinary learning program for junior high school students based on the science, technology, and society (STS) approach. The program emphasizes the macro–micro view of materials and consolidates understanding of the structures of materials through the context of fibers. Its aims are to construct the basic concepts of the structures, properties, and applications of materials and the relationship among them with regard to fabrics, threads, fibers, polymers, and composites; to cultivate scientific and technological literacy; and to develop students' learning and inquiry capabilities.The program interweaves knowledge and skills using scientific investigations, design processes, project-based learning, field trips, and STS dilemmas. It also offers knowledge integration tools such as a dynamic concept map and knowledge organizer. The design and instructional approach of the program we discuss may be helpful to other educators in developing STS-based learning materials.

How can one increase the awareness of teachers to the existence and importance of knowledge gained through physics education research (PER) and provide them with capabilities to use it? How can one enrich teachers' physics knowledge and the related pedagogical content knowledge of topics singled out by PER? In this paper we describe a professional development model that attempts to respond to these needs. We report on a study of the model's implementation in a program for 22 high-school experienced physics teachers. In this program teachers (in teams of 5-6) developed during a year and a half (about 330 h), several lessons (minimodules) dealing with a topic identified as problematic by PER. The teachers employed a systematic research-based approach and used PER findings. The program consisted of three stages, each culminating with a miniconference: 1. Defining teaching and/or learning goals based on content analysis and diagnosis of students' prior knowledge. 2. Designing the lessons using PER-based instructional strategies. 3. Performing a small-scale research study that accompanies the development process and publishing the results. We describe a case study of one of the groups and bring evidence that demonstrates how the workshop advanced: (a) Teachers' awareness of deficiencies in their own knowledge of physics and pedagogy, and their perceptions about their students' knowledge; (b) teachers' knowledge of physics and physics pedagogy; (c) a systematic research-based approach to the design of lessons; (d) the formation of a community of practice; and (e) acquaintance with central findings of PER. There was a clear effect on teachers' practice in the context of the study as indicated by the materials brought to the workshop. The teachers also reported that they continued to use the insights gained, mainly in the topics that were investigated by themselves and by their peers.

A new avenue of teaching the structure of materials is possible as a result of the development of high-resolution microscopes such as the scanning tunneling microscope (STM), which enables inspection of materials at atomic-level resolution. The purpose of this exploratory study was to examine the feasibility and potential contribution of using the STM as a learning tool in junior high school (JHS) to support instruction about the particulate nature of matter. Fifteen JHS science teachers and 60 students visited a materials research laboratory. After hearing a short introduction about the functions of the STM and its applications, the teachers and students performed several tasks. The results showed that although the teachers were concerned about possible difficulties in using the STM with JHS students, this activity contributed to the students' understanding of the particulate nature of matter and to their conviction of its existence. Students who demonstrated a particulate conception of matter succeeded in "seeing" atoms, although what they actually saw were bright and dark areas. Students who did not demonstrate a particulate conception of matter before the STM activity, were more convinced about the existence of atoms after the activity.

This study investigates the changes in junior high school (JHS) students' conceptions of the structure of matter as they study the subject of "materials" using a new curriculum in Science and Technology. The new instructional method is based on a student-centered constructivistic model and on a "spiral" approach to the learning of fundamental concepts. The sample consisted of an experimental group of 1,084 JHS students who studied "materials" according to the new curriculum, and a comparison group of 218 JHS students who studied this subject according to a traditional curriculum. Questionnaires, in which students were asked to represent the structure of several materials in words and pictures, were administered five times during a 3-year period. The results indicate three main mental models regarding students' conceptions of the structure of matter: Model A-materials are continuous substances; Model B-substances consist of particles; and Model C-substances consist of various molecules. The experimental group underwent a process of conceptual change regarding the structure of materials: More than 80% of the students moved from model A to model B, and 50% succeeded to move on to model C. (Contains 16 references.) (Author/YDS) Reproductions supplied by EDRS are the best that can be made from the original document.

This study contrasted spontaneous and reflective knowledge integration instruction delivered using a computer learning environment to enhance understanding of displaced volume. Both forms of instruction provided animated experiments and required students to predict outcomes, observe results, and explain their ideas. In addition, the reflective instruction diagnosed specific inconsistencies in student reasoning and encouraged students to reflect on these dilemmas as well as to construct general principles. We distinguished the impact of instruction on students who believed scientific phenomena are governed by principles (cohesive beliefs) versus students who believed that science is a collection of unrelated "facts" (dissociated beliefs). Students typically held multiple models of displacement, using different explanations depending on the form of assessment. For example, we found that 17% of these middle school students made accurate predictions about displacement experiments prior to instruction and 25% could construct an accurate general principle. However, only 12% consistently used the same explanation across assessments. After instruction, students were more accurate and more consistent: over 50% accurately predicted experimental outcomes, 79% gave an accurate general principle, and about 40% gave consistent responses. We found no advantages for enhanced animations over straightforward animated experiments. The reflective integration instruction led to more substantial long-term changes in student understanding than did spontaneous integration instruction. Furthermore, on a delayed posttest we found that students with cohesive beliefs not only sustained their understanding of displaced volume, but, when exposed to reflective integration instruction, actually continued to construct more predictive views following instruction. In contrast, students with dissociated beliefs made no long-term progress independent of the form of instruction.

This study formed part of a project aimed at revising the instructional approach for geometrical optics in the 10th grade. The instructional intervention was based on the extensive use of a diagrammatic representation as a descriptive, explanatory, and problem-solving tool in the doman. The purpose of this was to elicit the conceptions and representations of light propagation, image formation, and sight typical to preinstruction learners, with special attention to identifying precursors of problematic features of postinstruction students' knowledge. The premise for this study was that the difficulties students have before, during, and after traditional instruction with respect to representing optical phenomena have their origins in the fragmented prescientific knowledge constructed on the basis of experience. We believe that the difficulties persist because the key factors leading to fragmentation are not usually addressed and remedied. The main findings of the study indicate that (a) preinstruction students display some familiarity with optical systems, light propagation, and illumination patterns; (b) student-generated graphical representations describing and explaining optical phenomena display some features of formal ray tracing; (c) preinstruction students have not developed a consistent descriptive and explanatory model for light propagation; and (d) the context of sight seems to have a confounding effect on the establishment of a unified prior model for optical phenomena.

This publication is a collection of selected papers from the conference on science education in developing countries. The goals of this conference were to review past experiences about theory and practice in science education in both developed and developing countries, identify factors influencing successful practice around the world, distinguish priorities for science education in the 21st century, and develop a plan for action for achieving these priorities. The overview chapter which is based mainly on the Keynote addresses and Plenary sessions focuses on the following themes: goals and needs in science education, a look at the educational system, a look at the learner and the teacher, and assessment and feedback in science education. The papers included reflect a number of important issues relating to the nature of contemporary science education research and its implication for practice, whether in a developed or in a developing country. The chapters are organized around the main conference strands: The Learner, The Teacher, The Classroom, and the Curriculum. (JRH)

Graphic representations are the main and sometimes the only effective way of communication in the domain of Geometrical Optics. Many of the conceptual difficulties students have in this domain are related to the interpretation of these representations. RAY is an open graphic interface that was designed to address these problems, serving as a teaching aid in class and as a learning environment for students. The program enables the user to create and to control various optical components such as mirrors, lenses and prisms, to produce simulated ray diagrams and to analyze them with a set of graphic tools. Since any optical setup can be easily created and explored, extensive qualitative analysis can be performed during the study, dealing with many examples of ray diagrams. Program design enables the implementation of various approaches to learning and teaching, including the ability to combine the theory and its formal representations with real demonstrations and experiments.

מטרה: גילוי קשיים של תלמידים בהבנת תגובות כימיות. נבדקים: ניסוי 1: 337 תלמידים מעל גיל 15 הלומדים בבתי-ספר תיכון בארץ. ניסוי 2: 994 תלמידים כיתה י'. ניסוי 3: 1100 תלמידי כיתה י"ב. שיטה: לתלמידים הוצגו משוואות המייצגות תגובות כימיות, והם נתבקשו להסביר את המשוואות באמצעות ציורים. לתלמידי כיתה י"ב הועבר מבחן אמריקאי העוסק במספר נושאים הנלמדים בבית-ספר תיכון. מן הממצאים: א) לתלמידים קשיים בתפישת האופי האינטראקטיבי של תגובה כימית. ב) יותר מחצי התלמידים מציירים רק יחידה אחת. ג) אפילו בסוף הלימודים בבית-ספר תיכון יש למספר תלמידים קשיים בהבנת היבטים בסיסיים של תגובה כימית.

The function concept, one of the basic concepts of mathematics, constitutes a major part of the school curriculum in many contemporary programs. "The development of a sound understanding of the function concept provides a solid cornerstone on which to build additional mathematical concepts in later courses".