This study investigates students’ conceptions of the carbon cycle with regard to the components they believe to be relevant to the carbon cycle, how they interrelate these components, the ways in which they trace carbon atoms, and the different levels of biological organisation they consider when doing so. A total of 142 students aged 13–16 years (grades 8–10) participated in the study. A total of 130 students completed the diagnostic task, and an additional 12 students completed both the diagnostic task and were interviewed. The primary results show that the students identified few components of the carbon cycle, tended to trace carbon atoms exclusively at the level of the organism, and had difficulties identifying organic carbon compounds, especially during processes in which carbon compounds are transformed. Considering the main educational implications, we recommend using an instructional strategy that traces carbon atoms across the different levels of biological organisation whilst connecting fragmented knowledge by integrating knowledge from physiology, biochemistry and ecology when teaching the carbon cycle.

This study investigated factors influencing teachers’ intention and willingness to teach about cancer in the context of the theory of planned behaviour. Because teaching about cancer is mandatory in Germany, we compared n=355 teachers’ intention to teach about cancer under mandatory conditions and their willingness to teach about cancer if they had free choice. Teachers signalled strong intention and a strong willingness to teach about cancer. Teachers did not perceive teaching about cancer to be a burden and strongly considered it to be necessary. Structural equation modelling showed that perceived autonomy was the only significant predictor of teachers’ intention, whereas attitude towards the perceived necessity to teach about cancer, attitude towards the perceived burden of teaching about cancer and social norm were significant predictors of willingness. We attributed these differences to the observation of a ceiling effect for intention but not for willingness. There were systematic differences among the variables predicting teachers’ intention and willingness depending on whether the teachers had personal experience with cancer. Indirect measures yielded insights into which teacher beliefs affected the direct measures. We discuss implications for professional development, such as reducing the burden of teaching about cancer by adequately addressing emotionally-charged classroom situations.

Students often have misconceptions about terrestrial carbon flows and there is a lack of coherence in students’ explanations regarding the different levels of biological organisation at which these processes occur. In this study, problem-based teaching materials on the topic of terrestrial carbon flows were developed and tested with 15 students 18–19 years old (grade 12) using a pre/post-test design. Students focused on specific carbon flows in an ecosystem at the macro level (e.g. CO₂ fixation and heterotrophic respiration) including specific related concepts at the micro level (e.g. photosynthesis and cellular respiration). The findings indicate that the teaching materials improved the students’ understanding of terrestrial carbon flows and their ability to reason across the different levels of biological organisation. On the basis of these findings, implications for teaching terrestrial carbon flows in biological education are discussed.

Teachers’ beliefs about science teaching vary greatly. To analyze the relationships between teachers’ beliefs and other variables related to teaching and learning, researchers can use the following two options: single item belief models or belief scales. In this study, we compared both models in the context of teachers’ beliefs regarding teaching about cancer. Although both models exhibited a good model fit, each approach had both advantages and disadvantages when we judged the modelling approaches in terms of fulfilling the requirements of common psychometric standards and adequately acknowledging the diversity of different beliefs. We discuss the predictive value of both models and their contribution to planning belief-based interventions for cancer education. We argue that researchers should combine the advantages of single item and scale models when analyzing the diversity of teachers’ beliefs.