Content-Related Knowledge of Biology Teachers from Secondary Schools: Structure and learning opportunities

Teachers’ content-related knowledge is a key factor influencing the learning progress of students. Different models of content-related knowledge have been proposed by educational researchers; most of them take into account three categories: content knowledge, pedagogical content knowledge, and curricular knowledge. As there is no consensus about the empirical separability (i.e. empirical structure) of content-related knowledge yet, a total of 134 biology teachers from secondary schools completed three tests which were to capture each of the three categories of content-related knowledge. The empirical structure of content-related knowledge was analyzed by Rasch analysis, which suggests content-related knowledge to be composed of (1) content knowledge, (2) pedagogical content knowledge, and (3) curricular knowledge. Pedagogical content knowledge and curricular knowledge are highly related (r_latent?=?.70). The latent correlations between content knowledge and pedagogical content knowledge (r_latent?=?.48)—and curricular knowledge, respectively (r_latent?=?.35)—are moderate to low (all ps?<?.001). Beyond the empirical structure of content-related knowledge, different learning opportunities for teachers were investigated with regard to their relationship to content knowledge, pedagogical content knowledge, and curricular knowledge acquisition. Our results show that an in-depth training in teacher education, professional development, and teacher self-study are positively related to particular categories of content-related knowledge. Furthermore, our results indicate that teaching experience is negatively related to curricular knowledge, compared to no significant relationship with content knowledge and pedagogical content knowledge.     

Understanding the Greenhouse Effect by Embodiment – Analysing and Using Students' and Scientists' Conceptual Resources

Over the last 20 years, science education studies have reported that there are very different understandings among students of science regarding the key aspects of climate change. We used the cognitive linguistic framework of experientialism to shed new light on this valuable pool of studies to identify the conceptual resources of understanding climate change. In our study, we interviewed 35 secondary school students on their understanding of the greenhouse effect and analysed the conceptions of climate scientists as drawn from textbooks and research reports. We analysed all data by metaphor analysis and qualitative content analysis to gain insight into students' and scientists' resources for understanding. In our analysis, we found that students and scientists refer to the same schemata to understand the greenhouse effect. We categorised their conceptions into three different principles the conceptions are based on: warming by more input, warming by less output, and warming by a new equilibrium. By interrelating students' and scientists' conceptions, we identified the students' learning demand: First, our students were afforded with experiences regarding the interactions of electromagnetic radiation and CO₂. Second, our students reflected about the experience-based schemata they use as source domains for metaphorical understanding of the greenhouse effect. By uncovering the—mostly unconscious—deployed schemata, we gave students access to their source domains. We implemented these teaching guidelines in interventions and evaluated them in teaching experiments to develop evidence-based and theory-guided learning activities on the greenhouse effect.     

Primary Education in Sub-Saharan Africa--a moral issue,an economic matter,or both?

Generally, it is argued that economic factors explain changes in literacy and enrolment rates in sub-Saharan Africa. This article demonstrates that educational indicators vary as much with religious factors, i.e. degree of Islamisation and Christianisation, as with economic factors. Forty years ago, strongly Christianised countries had higher rates of literacy and primary school enrolment than strongly Islamised countries, regardless of economic level, typpe of state and colonial background, and they still have. The article ends with a number of assumptions which can serve as an agenda for research on educational development in sub-Saharan Africa.     

Output-sensitive autocompletion search

We consider the following autocompletion search scenario: imagine a user of a search engine typing a query; then with every keystroke display those completions of the last query word that would lead to the best hits, and also display the best such hits. The following problem is at the core of this feature: for a fixed document collection, given a set D of documents, and an alphabetical range W of words, compute the set of all word-in-document pairs (w, d) from the collection such that w ∈ W and d ∈ D. We present a new data structure with the help of which such autocompletion queries can be processed, on the average, in time linear in the input plus output size, independent of the size of the underlying document collection. At the same time, our data structure uses no more space than an inverted index. Actual query processing times on a large test collection correlate almost perfectly with our theoretical bound.

Radicalism in composition pedagogy

For the Record

Radicalism in composition pedagogy     

Einstellungen,Motivation und Selbstwirksamkeit von Lehrkräften

Teachers’ attitudes, motivation and self-efficacy are aspects of their professional competence affecting students’ motivation and learning via instructional behavior. In the present study, school type-specific differences in these teacher competencies and their relation to instruction when teaching with texts and integrated pictures are analyzed, further focusing on effects of school subject and teaching experience. Teachers (N?=?265) of primary school, lower and upper track secondary school filled in questionnaires. Primary school teachers were less intrinsically motivated to teach text-picture integration than secondary school teachers. They showed more negative attitudes towards texts with pictures than upper track teachers and avoided discussing the picture to a higher degree. All teacher characteristics predicted instructional behavior, further school type-specific effects of the subject occurred. The results provide starting points for teacher training and the potential for further research concerning the support of students in class.