Entwicklung und Einsatz von neuartigen Methoden zur Erfassung und Analyse experimenteller Prozesse

Büsch, Leonard; Heinke, Heidrun (Thesis advisor); Riese, Josef (Thesis advisor)

Aachen : RWTH Aachen University (2021)
Dissertation / PhD Thesis

Dissertation, RWTH Aachen University, 2021

Abstract

German educational curricula point out hands-on-experiments as an essential method of scientific work. Therefore, from a didactic point of view, it is only logical to place the processes in the area of experimentation and their development in the focus of didactic research work. A detailed evaluation of the handling of physical experiments by learners turns out to be very difficult, however, because the instruments for observation currently either do not allow real experiments or are extremely complex to evaluate and therefore only allow a small number of test subjects. In order to reduce the discrepancy between the lack of observation and analysis instruments and the ambition to evaluate experimental skills, two new methods of recording experimental processes have been tested in a hands-on laboratory experiment on radioactivity (confirmation of the effect of distance and absorption) at RWTH Aachen University. This enabled us to document over 300 students’ typical processes for carrying out and evaluating the experiment in the 2016/17 winter semester. The recording methods used in this thesis include, on the one hand, the logging of the experiments with smartpens, which allows a time-efficient identification and recording of process-relevant situations. On the other hand, an object-focused measuring instrument based on the Arduino microcontroller and suitable sensors was developed, which collects the procedural object data in the experiment, which enables a reconstruction of the experimental processes. The new survey approach of the object-focused recording of experimental processes as well as the still young technology of the smartpen make it possible to counter the previous survey problems and to develop new instruments to close the previous diagnostic gap. The present work contains detailed descriptions of the measuring instruments used, which can also be adapted to new experimental scenarios and further developed. The combination of the two measuring instruments gave a deep insight into the approaches of individual test teams when experimenting. At the same time, the methods allow the use of very time-efficient evaluation routines, so that larger numbers of test persons could participate. This opened up access to a wide range of experimental approaches that could be compared with one another. This created a basis for assessing the quality of the procedures. The successful testing of the survey instruments used allowed the identification of various process-relevant features and characteristic values. Some essential characteristics could be described in this work: It was observed that the variable control strategy was adhered to predominantly over all partial tests and that many test teams first carried out test measurements at the beginning of a new measurement task. It was also found that the measurement time intervals tended to be larger for larger distances and absorber thicknesses, which is considered to be useful in the context of the reliability of the measurement data. The data collected also allow statements to be made about the extent to which the independent variable was varied in a systematic way. Sankey diagrams made it possible to identify and describe developments in the procedures based on the features presented over the entire course of the experiment. In order to specifically show differences in the implementation, an intervention study was also carried out within the scope of this work, in which the student teams were provided with various experiment instructions. On the basis of the evaluation methods and the results, the readers should get an impression of the added value that the presented recording methods offer.