Purpose: This study aims to investigate how physical education teachers analyze their students’ swimming skills. Particular attention is given to information gathering within the diagnostic process. Methods: Data were collected from a quantitative online survey of German physical education teachers from primary and secondary schools (n = 551). This survey’s questionnaire is based on evaluated statements from a qualitative interview study (n = 10). Findings: Teachers’ diagnostic approaches vary greatly and differ in terms of quality criteria and usability. The predominant method used is movement observation, but 50.3% of the teachers do it rather rarely or without the use of criteria. Many of them (63.8%) would like to be supported by a diagnostic tool for the analysis of swimming skills. Discussion/Conclusion: It has been concluded that an accurate analysis of the students’ swimming skills as a precondition for adaptive lesson structuring is not achieved. It is necessary to determine whether a diagnostic tool could improve this process.

目的：本研究旨在调查体育教师如何分析学生的游泳技能。特别注意诊断过程中的信息收集。方法：数据来自对德国中小学体育教师的定量在线调查（ n  = 551）。本次调查的问卷基于定性访谈研究的评估陈述（ n  = 10）。研究结果：教师的诊断方法差异很大，并且在质量标准和可用性方面也有所不同。使用的主要方法是运动观察，但 50.3% 的教师很少或没有使用标准。他们中的许多人（63.8%）希望得到用于分析游泳技能的诊断工具的支持。讨论/结论：得出的结论是，对学生游泳技能的准确分析作为适应性课程结构的前提条件尚未实现。有必要确定诊断工具是否可以改进此过程。