Page 147 - Getting the Picture Modeling and Simulation in Secondary Computer Science Education

Students’ Understanding and Difficulties
specifically on verification and validation and we portrayed the students’ activities and difficulties in great detail.
In this study, we asked students to extensively reflect on their models in terms of contentment with them, and thus we limited the scope of students’ responses. To our surprise, several students declared lack of confidence in models in general — a thought we did not encounter in our previous study.
6.5.3 Reflection on the methodology
In this study, similarly to the one from 2016 (see chapter 3), a small number of students was involved which allowed us to perform an in-depth investigation of their understanding of model validation. It would be interesting to repeat the study at larger scale to see if similar practices regarding model validation can be observed.
All of the students involved in this study were in the final stages of their pre-
university education, which implies that they probably experienced less difficulties
that can be expected from younger students or those attending the senior general
secondary education — an assertion corroborated by our findings from the study
on assessment instrument (see chapter 5). Furthermore, we did not observe the
students at work and only relied on the project documentation they turned in
and on what they reported themselves during the interviews. Even though the
researcher interviewing the students was their teacher, we have no reason to 6 expect this fact influenced their responses.
Finally, we believe that our findings help identify both the improvements and weaknesses in the teaching materials used — as compared to teaching materials used for the previous study — and will inform the further development of the teaching materials, teaching methods and teacher training. We suggest to put more emphasis on teaching a small selection of validation techniques and giving students more guidance in using them, while simultaneously making them aware of the availability of a whole range of additional validation techniques which are not easily used within the constraints of a limited CS course in general secondary education.
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