Effect of bead and illustrations models on high school students' achievement in molecular genetics

Our main goal in this study was to explore whether the use of models in molecular genetics instruction in high school can contribute to students' understanding of concepts and processes in genetics. Three comparable groups of 11th and 12th graders participated: The control group (116 students) was taught in the traditional lecture format, while the others received instructions which integrated a bead model (71 students), or an illustration model (71 students). Similar instructions and the same guiding questions accompanied the two models. We used three instruments: a multiple‐choice and an open‐ended written questionnaire, as well as personal interviews. Five of the multiple‐choice questions were also given to students before receiving their genetics instruction (pretest). We found that students who used one of the two types of models improved their knowledge in molecular genetics compared to the control group. However, the open‐ended questions revealed that bead model activity was significantly more effective than illustration activity. On the basis of these findings we conclude that, though it is advisable to use a three‐dimensional model, such as the bead model, engaging students in activities with illustrations can still improve their achievement in comparison to traditional instruction. © 2006 Wiley Periodicals, Inc. J Res Sci Teach 43: 500–529, 2006     

Pass the owl: Encouraging participation with a hot potato

This article provides a suggestion for encouraging an appropriate level of participation from all students in a small class or tutorial discussion.     

Points for Debate: God's Child

Considerable resources and intellectual attention have focused on seeking to raise the status of teaching in higher education over the last two decades. Initiatives at an institutional level have included the funding of pedagogic research, teaching awards and the creation of teaching professorships. In a broader context, the scholarship of teaching and learning movement has campaigned for a reconfigured and more inclusive understanding of scholarship. However, despite the good intentions of these initiatives, the effect been to lower still further the status of teaching, bifurcating universities between ‘teaching’ and ‘research’. It is argued that efforts should instead be directed at integrating academic practice as a more effective way of raising the status of teaching.     

Signaling the omission of a response-contingent outcome reduces discriminative control

The effect of training a positive discriminative stimulus (S+ ) as a signal for the nonreinforcement of an instrumental response (S?) on the ability of that stimulus to evoke its original instrumental response was examined in three experiments using rats. In all three experiments, two different stimuli were established as S+s for different response-outcome relations. In Experiment 1, an S+ was less effective in controlling its original response after it had undergone training as an S? for a new response that earned the same outcome than it was after training as an S? for a response that earned a different outcome. Experiment 2 established that this effect was not mediated by Pavlovian inhibitory conditioning produced by the negative correlation between the S+ and the outcome during S? training. Simply arranging a negative correlation between S+ and the outcome whose occurrence it had previously signaled did not impair the ability of that S+ to elicit its original response. In Experiment 3, the response-evoking properties of an S+ were found to be undermined by using the S+ as a signal for the simple extinction of a new response trained with the same outcome, but not with a different outcome. These results suggest that positive discriminative stimuli use their associations with the outcomes earned in their presence to control the responses that earned those outcomes.     

Improving preservice chemistry teachers’ content knowledge through intervention activities

ABSTRACT

The effect of intervention activities on the chemistry content knowledge of 92 preservice chemistry teachers (PSCT) was examined via a pre and post true/false with confidence level test focusing on ionisation energy values and the use of a common alternative conception (AC). Data were collected from three cohorts of PSCT each engaged in a one year full-time university-based teacher education programme. Comparison of pre-and post-test responses and discrimination differences between responses for each PSCT were used to identify the use of the AC and hence the efficacy of the intervention activities. Interviews with 14 of these PSCT allowed triangulation of the data. Findings suggest that the activities allow 71% of PSCT to identify this AC as non-scientific or become more confident in doing so. Interview data indicate that this rejection of this AC is sustained for 9 of the 11 PSCT whose test data indicated improvement. These data have implications for teacher education such that 2 hour intervention sessions can offer the opportunity for PSCT to develop their subject matter knowledge. As the accurate application of electrostatic concepts to electrons has wider application to bonding, these interventions offer PSCT more accurate chemical subject knowledge resources to draw on in their teaching.     

Teacher's in-Service Education: A Proposal for Turning Teachers Into Teacher-Researchers

The paper focuses on the contribution of action research to teachers' in-service education at elementary schools in the Rio de Janeiro local system of education, linking thought and action indissolubly. This involves inviting teachers and learners to question their own practice, in their own process of building up citizenship, while striving to recover their place in a society that limits and makes their social relations difficult. The development of action research at the Faculty of Education in Rio de Janeiro State University, Rio de Janeiro, Brazil, has brought to light ethical, scientific and political questions in the school system.     

Information,Instruction, and Learning: A Hypermedia Perspective

Hypermedia as defined by Osgood (1987) is a tool for linking nonlinear information presented in the form of graphics, animation, video, and sound. One important question for instructional designers regarding hypermedia is how it can be used as an instructional or learning tool that enhances rather than inhibits learning. Creating hypermedia applications is a quick and easy alternative to creating courseware with older authoring systems and languages which took many hours to learn. This ease of application creation, combined with a tremendous increase in information available to our society, has resulted in a proliferation of hypermedia databases in school, university, and industry settings that is gradually moving into homes. Many of these databases are simply information media. This paper identifies important issues related to classifying a hypermedia–based information system appropriately. Based on a discussion of these issues, a call for systematic research which clarifies the role that hypermedia–based information systems can and should play in an instructional or learning environment is set forth.