Journal of Baltic Science Education

1-2

Authors: Editorial Board

Cover, JBSE, Vol. 6, No. 3, 2007

5-15

Authors: Aleksandriya Gendjova

Тhis study investigates the effect of home experiments on students’ interest in chemistry. The subject of the study are two groups of a total of 213 seventh graders. The control group performed traditional experiments in the classroom, while the experimental group an additional set of different home experiments. To research students’ interest the following methods were used: observation, testing, survey. Results show that students from the experimental group acquired higher level of knowledge, expressed positive attitudes toward the subject, and a desire to do extra activities.This results indicate that use of home experiments to connect chemistry with the real life of the students creates the conditions for an increased students’ interest.

27-33

Authors: Zoltán Tóth, Lajos Ludányi

This study compares Hungarian 7th to 11th graders’ thinking patterns in describing an ion. The combination of phenomenography and knowledge space theory was used as evaluation method to explore students’ reasoning and to follow the change in students’ cognitive structures. According to the phenomenographic analysis of the responses, three main categories, ‘ions are particles’, ‘charge of ions’ and ‘formation of ions’, were identified. Connections between these categories were determined by adapting knowledge space theory to the hierarchy of categories. Results showed a typical shape of the process of conceptual change. The initial model for representation of students’ knowledge structure is a simple one but during the instruction this model becomes more complex and finally ‘crystallises’ the new model. In the initial model, the ‘charge of ions’ category was independent of the ‘formation of ions’ category, and these both categories were built on the category ‘ions are particles’. Significant change in connections among categories could be detected in 8th grade. From 8th grade the category ‘ions are particles’ as basic knowledge was changed into the category ‘charge of ions’. At the end of the instruction (in 11th grade) – after mixing these models in 9th and 10th grades – a double model with basic category ‘charge of ions’ was found for representation of students’ thinking patterns in describing an ion.

44-54

Authors: Karin Stolpe, Helge Strömdahl

In this study three different patterns of reasoning have been identified: linear, star and combined reasoning. As six student teachers were working on a contextualized task on heat and temperature they showed these different patterns of reasoning during an interview situation. The data was analysed using reasoning maps. The patterns are also discussed in relation to the students’ subject matter knowledge in this specific area. There are indications that the reasoning pattern is dependent on what kind of scientific subject matter knowledge the student reveals. Star and combined reasoning make it possible to look at the task from different angles and thereby develop fragmented knowledge into more comprehensive knowledge.