Multiple representations in web-based learning of chemistry concepts

A new chemistry curriculum for secondary schools is currently under construction in the Netherlands, in which chemical knowledge will be embedded in contexts that show applications of chemistry in the society. Several research groups develop such modules and a committee appointed by the Dutch Ministry of Education advises about the chemical content and concepts.\ud A central issue in chemistry education is the relation between the real, molecular and symbolic world. Skilled chemists switch easily between these worlds, but beginning students do not. They could get better results and will be more able to solve problems if they would make better connections between the three chemical worlds. The University of Twente has developed a series of lessons about the particle model. Included in this instruction material are animations of chemical processes at the molecular level. In the lessons students are supported and stimulated to make connections between the three chemical worlds. Students are shown the importance of new chemical knowledge in society. The mental images and the knowledge schemata of the students are investigated in this research. The students were interviewed before they received instruction, and after they received about half of the instruction. At the end of the instruction they were asked to make a concept map.\ud It appeared that the links between the real, molecular and symbolic world are not strengthened after the instruction. The students make more links between the real and symbolic world, but hardly connect these world to the molecular world or vice versa. There is still a gap between the students’ mental models and scientifically accepted models as represented in animations and illustrations in the instruction. Most students liked the animations in the instruction and mentioned them as strong point. It is therefore surprising that some students could not remember the animations when they were interviewed, whilst others their representations were about the same as the animations. Clearly, the effectiveness of the animations must be enhanced and more research is needed for this

Het veranderen van opvattingen van chemiedocenten door partici-patie in een ontwikkelnetwerk

Opvattingen over leren en onderwijzen spelen bij het handelen van docenten een grote rol. Omdat opvattingen diep geworteld zijn in de ervaringen van docenten blijken ze moeilijk te veranderen. Wil een curriculumverandering succesvol zijn dan moeten de opvattingen van docenten erbij worden betrokken.\ud Het invoeren van een vernieuwing kan gezien worden als een leerproces van docenten, waarin aandacht is voor vakinhoud en didactiek maar ook voor opvattingen. Een van de manieren om dit leerproces vorm en inhoud te geven is door het opzetten van netwerken van docenten. De netwerken ontwikkelen leermaterialen voor leerlingen en de deelnemers gebruiken deze materialen in hun onderwijs. Het netwerk kan worden gezien als een leergemeenschap.\ud De vraag in dit onderzoek is hoe de opvattingen van docenten door participatie in een ontwikkelnetwerk veranderen. De opvattingen van de docenten zijn daarvoor op drie momenten tijdens het ontwikkelproces vastgelegd, waarbij gebruik gemaakt is van meerdere instrumenten

Assessing teachers’ beliefs to facilitate the transition to a new chemistry curriculum: what do the teachers want?

In this article, we describe the results of a study of chemistry high school teachers’ beliefs (N = 7) of the chemistry curriculum and their roles, their beliefs on the teacher as developer of materials, and their beliefs about professional development. Teachers’ beliefs influence the implementation of a curriculum. We view the use of a new curriculum as a learning process, which should start at teachers’ prior knowledge and beliefs. The results reveal that it is possible to develop a new curriculum in which teachers’ beliefs are taken as a starting point. Promising approaches to prepare teachers for a new curriculum is to let them (co)develop and use curriculum materials: It creates ownership, and strengthens and develops teachers’ pedagogical content knowledge (PCK)

The effects of the design and development of a chemistry curriculum reform on teachers’ professional growth: a case study

A curriculum innovation requires new learning material for students and a preparation program for teachers, in which teacher learning is a key ingredient. In this paper we describe how three experienced teachers, involved in the development and subsequent classroom enactment of student learning material for context-based chemistry education, professionalized. For data collection a questionnaire, three interviews and discussion transcripts were used. Our results show that: (a) teachers, cooperating in a network under supervision of an expert, can develop innovative learning material; (b) the development of learning material can be seen as a powerful program to prepare teachers for an innovation; and (c) teachers’ knowledge increased in all five pedagogical content knowledge domains during the development and class enactment phases