Argumentation on Alternative Reaction Pathways in Organic Chemistry
In organic chemistry, building arguments and applying concept knowledge on reaction mechanisms are essential skills, as these skills are needed whenever decisions and judgements are made, and alternatives are weighed. Applying concept knowledge when building arguments leads to the generation of a deeper understanding of the relevant content as ... analytical thinking is activated. Research has revealed that students experience challenges when they build arguments or use concept knowledge. However, there has been little evidence on how to support students’ individual challenges in building arguments. Therefore, to address this gap, the first step was to design a task sequence that challenges students’ typical problem-solving approach of rote memorization to shift their approach to more analytical thinking, which is the basis for building well-grounded arguments. For this purpose, we designed tasks in which twenty-nine organic chemistry students could experience a cognitive conflict by reflecting on alternative reaction pathways, aiming to promote more analytical thinking. The analysis revealed that students were able to become aware of and critically reflect on their problem-solving approach. Besides fostering more analytical thinking, we investigated students’ argumentation structure when judging the plausibility of alternative reaction pathways in terms of the claim-evidence-reasoning model. It was investigated to which extent students used evidence and reasoning in building arguments and how they justified a change in their claim by weighing the alternative reaction pathways. The results illustrate that students need support in structuring their arguments and in applying concept knowledge to build chemically sound arguments. In order to adequately address the diagnosed challenges when building arguments (i.e., structuring arguments and applying concept knowledge), an adaptive scaffold was designed that was tailored to students’ individual needs. Therefore, in a first step, students received a diagnostic scaffold to support them in building arguments while their performance of structuring arguments and applying concept knowledge was analyzed. In the second part, each student received a scaffold adapted to the area in which they experienced the greatest challenges. The evaluation of the scaffold revealed that the students expressed a positive attitude towards the adaptive scaffold and stated that they had engaged more intensively with the tasks. In addition to the promising student feedback, a quantitative analysis was conducted to examine students’ performance on the diagnostic and adapted scaffold. The comparison showed that the adapted scaffolds improved students’ performance in the respective areas of support (i.e., structuring arguments and applying concept knowledge) and that the gap regarding to students’ performance was narrowed. In this dissertation, it is demonstrated that building arguments on alternative reaction pathways provides new insights into diagnosing the building of arguments and the challenges students experience as a consequence thereof, and into supporting students regarding their individual challenges with an adaptive scaffold.