One of the most central tenets of chemistry education is developing an understanding of the processes that involve the Transformation of Matter. Current German curricula postulate content-related abilities (Kompetenzen) that are expected to be achieved by secondary students when graduating from the lower secondary level at grade 10. These abilities can further be differentiated as relating to either structural aspects of matter or to aspects of chemical reaction. Little is known of how Kompetenzen in these two fields develop over time on the lower secondary level. This study aims at elucidating this development by suggesting a hypothetical learning progression for the lower secondary level. This learning progression is visualised as a Strand Map and is investigated using methods from three statistical approaches: Rasch-analyses, Classical Test Theory, and Bayesian Networks. Concurrent data from all three strands of analyses inform the evaluation of the learning progression and support the notion that an understanding of the Transformation of Matter relies on interrelated Kompetenzen to conceptualize Structure of Matter and Chemical Reaction. Moreover, Bayesian networks underline that there is more than one progression when learning about chemistry on the lower secondary level.

中文翻译：

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在初中阶段评估“物质转化”的学习进度

化学教育的最主要宗旨之一是加深对涉及物质转化的过程的理解。当前的德语课程假定中学生从10年级的初中毕业时将达到与内容相关的能力（Kompetenzen）。这些能力可以进一步区分为与物质的结构方面或与化学方面有关反应。人们对Kompetenzen的了解甚少在这两个领域中，随着时间的推移，初中水平会不断提高。这项研究旨在通过建议低中学历的假设学习进展来阐明这种发展。该学习进度显示为“链图”，并使用三种统计方法的方法进行了研究：Rasch分析，经典测试理论和贝叶斯网络。来自所有三个分析阶段的并发数据为学习进展的评估提供了依据，并支持以下观点：对物质转化的理解依赖于相互关联的Kompetenzen来概念化物质和化学反应的概念。此外，贝叶斯网络强调，在中学以下阶段学习化学时，会有多个进步。