The effectiveness of student team-achievement division (STAD) for teaching high school chemistry in the United Arab Emirates

Education in the United Arab Emirates (UAE) faces major problems which may hinder its future development. These include low achievement in science and a negative attitude toward science subjects, which have resulted in a high number of student dropouts from the science track in high school. It is believed among UAE educators that the main reason is the way science that has been taught in its schools. A solution to this problem depends on finding effective teaching methods, which maintain student achievement, improve students' attitude and provide opportunities to develop essential scientific skills. The effectiveness of Student Team-Achievement Division (STAD) for teaching science to high school classes in the UAE was investigated. The sample was selected randomly. A representative group of UAE high school students was chosen from the northern province, which includes urban areas, and from the eastern province, which includes rural areas. The study involved sixteen tenth grade classes. During the second semester of the academic year 1998/1999, three units in the chemistry curriculum were covered. This study was designed to investigate the effectiveness of STAD in teaching high school chemistry in the UAE and to find out which groups, gender, area, and ability benefitted most.     

External Visual Representations in Science Learning: The case of relations among system components

The present paper reports on a study that examined whether practical work can be said to have affective outcomes, and if so in what sense. The term ‘affective’ is used here to refer to the emotions, or feelings, engendered amongst pupils towards school science in general, or one of the sciences in particular. The study is based on 25 multi‐site case studies that employed a condensed fieldwork strategy. Data were collected, using tape‐recorded interviews and observational field notes, in a sample of practical lessons undertaken in English comprehensive (non‐selective) schools during Key Stages 3 and 4 (ages 11–14 years and 15–16 years, respectively). The findings suggest that whilst practical work generates short‐term engagement, it is relatively ineffective in generating motivation to study science post compulsion or longer‐term personal interest in the subject, although it is often claimed to do so. This suggests that those involved with science education need to develop a more realistic understanding of the limitations of practical work in the affective domain.     

Representational Classroom Practices that Contribute to Students’ Conceptual and Representational Understanding of Chemical Bonding

Understanding bonding is fundamental to success in chemistry. A number of alternative conceptions related to chemical bonding have been reported in the literature. Research suggests that many alternative conceptions held by chemistry students result from previous teaching; if teachers are explicit in the use of representations and explain their content-specific forms and functions, this might be avoided. The development of an understanding of and ability to use multiple representations is crucial to students’ understanding of chemical bonding. This paper draws on data from a larger study involving two Year 11 chemistry classes (n = 27, n = 22). It explores the contribution of explicit instruction about multiple representations to students’ understanding and representation of chemical bonding. The instructional strategies were documented using audio-recordings and the teacher-researcher’s reflection journal. Pre-test–post-test comparisons showed an improvement in conceptual understanding and representational competence. Analysis of the students’ texts provided further evidence of the students’ ability to use multiple representations to explain macroscopic phenomena on the molecular level. The findings suggest that explicit instruction about representational form and function contributes to the enhancement of representational competence and conceptual understanding of bonding in chemistry. However, the scaffolding strategies employed by the teacher play an important role in the learning process. This research has implications for professional development enhancing teachers’ approaches to these aspects of instruction around chemical bonding.     

The use of analogies in language teaching: Representing the content of teachers' practical knowledge

This study sought to determine how experienced language teachers use analogies to help students comprehend a text on the course of their regular teaching routines. It is assumed that analogies constitute one important component of the content of teachers' practical knowledge in the context of reading-comprehension instruction. The framework of the study drew from Shulman's notion of 'pedagogical content knowledge'; the perspective was the analogy-provider (e.g. teacher or textbook author). Eight lessons taught by eight different teachers were observed and analysed for the presence of analogies. The frequent use of analogies, continuously under discussion in the literature about science education, seems at least open to question. The research suggests that teacher education programmes for language teaching should include information about developing and evaluating instructional analogies.     

Students’ reported justifications for their representational choices in linear function problems: an interview study

Thirty-six secondary school students aged 14–16 were interviewed while they chose between a table, a graph or a formula to solve three linear function problems. The justifications for their choices were classified as (1) task-related if they explicitly mentioned the to-be-solved problem, (2) subject-related if students mentioned their own characteristics as representational users, (3) context-related if contextual features surrounding the choice were mentioned and (4) representation-related if formal characteristics of the representations were pointed out. Justifications were mostly task- and subject-related, although contextual and representational features also played an important role. Some students (reportedly) tried to reconcile different (task-, subject-, context- and representation-related) factors before selecting a representation, which was interpreted as an attempt to use their meta-representational competence to make appropriate representational choices. The influence of the didactical contract and the experimental contract on students’ representational choices, as well as the tensions between them, are also discussed.     

“中国美国新加坡”小学数学教材中的“分数定义”

选取中国、新加坡、美国的小学数学主流教材,比较教材中分数定义的相关内容。发现3个国家教材中出现的定义种类大体相同,都包含4种：份数定义、商的定义、数线定义、比的定义,但定义的表征形式及呈现顺序有很大不同,对中国的教材编写及教学设计有一定的借鉴意义。     

Assisting self-explanation prompts are more effective than open prompts when learning with multiple representations

Learning with multiple representations is usually employed in order to foster understanding. However, it also imposes high demands on the learners and often does not lead to the expected results, especially because the learners do not integrate the different representations. Thus, it is necessary to support the learners’ self-explanation activity, which concerns the integration and understanding of multiple representations. In the present experiment, we employed multi-representational worked-out examples and tested the effects of two types of self-explanation prompts as help procedures for integrating and understanding multiple representations. The participants (N = 62) learned about probability theory under three conditions: (a) open self-explanation prompts, (b) self-explanation prompts in an assistance-giving-assistance-withholding procedure (assisting self-explanation prompts), or (c) no prompts (control group). Both types of self-explanation prompts fostered procedural knowledge. This effect was mediated by self-explanations directed to domain principles. Conceptual knowledge was particularly fostered by assisting self-explanation prompts which was mediated by self-explanations on the rationale of a principle. Thus, for enhancing high-quality self-explanations and both procedural knowledge and conceptual understanding, we conclude that assisting self-explanation prompts should be provided. We call this the assisting self-explanation prompt effect which refers to the elicitation of high-quality self-explanations and the acquisition of deep understanding.     

The structure of students’ beliefs about the use of representations and their performance on the learning of fractions

Cognitive development of any concept is related with affective development. The present study investigates students’ beliefs about the use of different types of representation in understanding the concept of fractions and their self‐efficacy beliefs about their ability to transfer information between different types of representation, in relation to their performance on understanding the concept. Data were collected from 1701 students in Grade Five to Grade Eight. Results revealed that multiple‐representation flexibility, ability on solving problems with various modes of representation, beliefs about the use of representations and self‐efficacy beliefs about using them constructed an integrated model with strong interrelations in the different educational levels. Confirmatory factor analysis affirmed the existence of differential effects of multiple‐representation flexibility and problem‐solving ability in respect to cognitive performance and the existence of general beliefs and self‐efficacy beliefs about the use and the role of representations. Results suggested the invariance of this structure across primary (Grades Five and Six) and secondary education (Grades Seven and Eight). However, there are interesting differences concerning the interrelations among those cognitive and affective factors between primary and secondary education.     

Does multimedia learning theory extend to middle-school students?

The purpose of this study is to translate principles of multimedia learning from college-age readers to middle grade students, when reading science texts with a supporting diagram. In this experimental study, sixth-grade students (n = 180) were randomly assigned to display conditions before reading. Each student read two explanatory sciences passages, a life-science and a physical science text. Passages were accompanied by either no illustrations (control), illustrations of the cycle with labels for each part (parts), illustrations of the cycle with labels for each major process (steps), or illustrations showing the labels for each part and each major process (parts and steps). Additionally, there were two text conditions in which half of the students read standard text (control) and half read texts with cues which indicated to students when to access the diagrams (cued). Through ANOVA analysis, in the life-science text students showed modest improvement (partial η² = .18) from the addition of diagrams, with the parts diagram and the steps diagram outperforming the control. In the physical science text, students did not receive benefit from the diagrams. Findings did not replicate results from college-age readers to younger readers, nor between the two texts with younger readers. These results raise concern for the application of multimedia design theory to classroom practice.     

Encrypted objects and decryption processes: problem-solving with functions in a learning environment based on cryptography

This paper introduces an applied problem-solving task, set in the context of cryptography and embedded in a network of computer-based tools. This designed learning environment engaged students in a series of collaborative problem-solving activities intended to introduce the topic of functions through a set of linked representations. In a classroom-based study, students were asked to imagine themselves as cryptanalysts, and to collaborate with the other members of their small group on a series of increasingly difficult problem-solving tasks over several sessions. These tasks involved decrypting text messages that had been encrypted using polynomial functions as substitution ciphers. Drawing on the distinction between viewing functions as processes and as objects, the paper presents a detailed analysis of two groups’ developing fluency with regard to these tasks, and of the aspects of the function concept underlying their problem-solving approaches. Results of this study indicated that different levels of expertise with regard to the task environment reflected and required different aspects of functions, and thus represented distinct opportunities to engage those different aspects of the function concept.