Why school-related content knowledge for pre-service chemistry teachers should include basic concepts in organic chemistry

Goal

For this study the following research questions will be evaluated and answered:

1. How do the students solve the SRCK-tasks that were part of this study?

2. How do the students rate the relevance of the SRCK-tasks for their future profession?

3. What attitude do pre-service chemistry teachers have towards concepts in organic chemistry?

4. How do the students rate the usefulness of the anchoring concepts for solving tasks?

5. In what way do concepts build a bridge between university and school knowledge as defined by the SRCK-concept?

Sample

The expert rating of the task was conducted by six educators with experience in teaching organic chemistry.

For the rating of the tasks, students from the course “Organic Chemistry I” (bachelor) and from the course “PCK in chemistry” (master) participated. In the first round of rating (rating of two tasks), 16 students participated. They received 10 Euro as compensation for their time. In the second round (rating of the third task and focus group interview), five students (3 m, 2 f) participated. Two students were in their master studies and three in their bachelor studies. They received 20 Euro as compensation for their time. The students were informed about the goal of the study and the use of the data; ethical guidelines were followed. The approval of the institutional review board is not required at German universities.

Development and use of the questionnaires

For the expert rating a questionnaire was developed. The questionnaire consisted of a quantitative part with questions in a yes/no answering format and open questions to explain the reasons for answering the questions. The experts received two SRCK-tasks and an overview of the 10 Big Ideas after the ACCM (Raker et al., 2013). The experts should rate which big ideas are needed for solving the task at hand and explain their choice. The goal of the study was explained. Statistical data on the teaching and/or research experience were also collected. All questionnaires were coded to ensure that they could be assigned and compared.

Based on the results of the expert rating, the questionnaires for the students’ rating were developed. The tasks were rated using a questionnaire with a 4-item Likert scale (Allen & Seaman, 2007). For the perceived relevance of the tasks, the eight items from an existing questionnaire (Hermanns, 2020) were used. In addition, five items on the topic of concepts were added (see Table 2). The big ideas were rated with the same yes/no questions as in the expert rating. The students also explained their choice. The results of the expert rating were used to make a preselection of the ideas. For the first round, eight big ideas were included, for the second round 10. The students also had to solve the tasks.

The focus group interview

The focus group interview was conducted via an online conference tool. To ensure anonymity, the students did not use their camera and used when speaking a number that was assigned to them. For the interview, a manual with several questions belonging to four categories was developed and used (see Table 3).

The expert rating

For the expert rating, the two tasks from round 1 were used: “Johanna and Tim” and “schoolbook”. All experts teach organic chemistry; five also are researchers in this field. All experts use anchoring concepts in their courses. The information on the Big Ideas (Raker et al., 2013) was in their view not sufficient; this was taken into account by designing the questionnaires for the students. All descriptions of the Big Ideas were made anew and contained more information. The experts’ voting which Big Ideas are necessary for solving the tasks was compared with the view of the co-author (bachelor student). If the experts’ agreement was at least 50%, the Big Idea was included in the questionnaire. Only for one Big Idea there was no agreement between experts and co-author; the experts voted for including the Big Idea on “energy and thermodynamics” which the co-author wouldn’t have included. From their view this is not surprising, because organic chemistry courses seldom focus on this concept explicitly. For the first round (tasks 1 and 2) eight Big Ideas were rated as necessary, they were therefore included in the questionnaire. The Big Ideas “intermolecular forces” and “chemical equilibrium” were not included.

Research question 1: how do the students solve the SRCK-tasks that were part of this study?

The solutions of the students were analyzed according to Kuckartz (2016) using the method of qualitative content analysis. The coding of the solutions included three categories: predominantly wrong, partly correct and predominantly correct. Predominantly wrong means that the solution contains more wrong than right answers or is incomplete. Partly correct means that the solution contains more right than wrong answers or only few small mistakes. Predominantly correct are extensive right solutions. This assignment was done by both authors who did not differ from each other. Table 4 shows the results of this analysis.

As the results show, the tasks were mostly solved partly or predominantly correct. We therefore conclude that the students’ knowledge of organic chemistry is sufficient for the rating of the tasks and the concepts.

Research question 2: how do the students rate the relevance of the SRCK-tasks for their future profession?

Although the students’ rating of SRCK-tasks is known from the literature (Hermanns, 2020; Massolt & Borowski, 2018), we included the rating in this study. We wanted to know whether the students who participated in this study rated the tasks in a similar way as the students in previous studies. There it was shown that the students rated SRCK-tasks as relevant for their future profession. Table 5 shows the results of the rating in this study. For task 1, one student did not fill out the questionnaire. Therefore, N is here only 15.

Almost all ratings are in the same range as the ratings from the literature (Hermanns, 2020). The item “promotes my ability to communicate” was rated less well. This can be explained with the setting of the study. Because of the online teaching there was no direct communication between the students (as in the previous studies). Overall, it can be concluded that the students rated the tasks as being relevant for their future profession.

Research question 3: what attitude do pre-service chemistry teachers have towards concepts in organic chemistry?

Eleven students (out of 16) knew anchoring concepts at least partly from their university studies. Almost all students knew these concepts from a course they attended voluntarily in the winter term 2019/20 (name of the course and literature will be added after the reviewing process). However, in other courses anchoring concepts are not explicitly taught and applied as stated by the students. During the focus group interview the students argued that anchoring concepts should be an integral part of the courses in chemistry: “[they] would be helpful […] for the own structuring of the content, from new content”. They also rated concepts as being useful for their future profession and for their own teaching: “it is for students at school much more motivating, if they recognize a concept in a new context”.

In the questionnaire (for results see Table 7), the item “concepts in organic chemistry give an opportunity for better understanding the content” was rated between 3.47 till 3.80 (for the three tasks) and therefore between agree and strongly agree. It can therefore be concluded that anchoring concepts should be explicitly taught and applied in university courses in organic chemistry. The rating of the item “the included concepts are important for my future profession” which is rated between 3.40 till 3.62 and therefore also between agree and strongly agree supports this. However, the students are no experts on the use of concepts. The selection of the concepts they needed for the task was rated mostly as being not easy. The arithmetic means for the first two task were 2.27 and 2.88 and therefore in the range of “disagree”. For the third task the rating was better, but task 3 was solved only by five students (two in their master studies) who voluntarily agreed to solve another task. Most certainly that was those students that had less problems with the application of concepts. Overall, we hypothesize that the students did not have sufficient opportunity for training the application of concepts when solving tasks.

Research question 4: how do the students rate the usefulness of anchoring concepts for solving tasks?

The students selected the anchoring concepts they used for solving the task and explained their choice. The students’ explanations were coded using the method of qualitative content analysis (Kuckartz, 2016). For task 1, the inter coder reliability (Brennan & Prediger, 1981) for the concepts “atoms”, “bonds”, “structure and function” and “chemical reactions” was 87.9% and therefore sufficient. Table 6 shows the assignment of the answers to the anchoring concepts.

In the students’ assessment which anchoring concepts they used for solving the tasks there are some inconsistencies. Although 14 out of 16 students used structural formulas for solving task 1, only 25.0% chose the use of the concept “visualization” for this task. This is surprising because structural formulas are a model to describe what happens on the microscopic level. Because the students used their structural formulas in this way, they should have chosen this concept. This shows that the students don’t reflect which concepts they are using, most certainly because the application of concepts while solving tasks is unusual for them. This is supported by their rating that concepts were mostly no explicit part of their university studies. A comparison of the choice of concepts for the three tasks shows that the students used mostly the same concepts: “atoms”, “bonds”, “structure and function” and “chemical reactions”. The other concepts, especially “energy and thermodynamics” and “kinetics” are rated to be less important. The students don’t see the link between those concepts and organic chemistry as the following citation from the focus group interview shows: “I think that the concepts are sufficient for organic chemistry. I think the concepts go beyond organic chemistry, for example aspects as energy and thermodynamics or kinetics. I was a bit confused, because I thought, what does that have to do with organic chemistry?” One reason for this can be that such issues were no part of the courses in organic chemistry. The students would then rate especially those concepts as being useful that they connect with the content of their course. The usefulness of the concepts for solving the tasks was also rated by the students with the questionnaire. Table 7 shows the results.

Although the students rate anchoring concepts as being helpful for understanding the content, the rating of the item “the concepts support the solving of the task” was only between 2.60 and 3.31 (disagree till agree). As discussed before it can be assumed that the students did not have sufficient opportunity for applying concepts while solving tasks. This is supported by the rating of the item “the selection of the concepts that were used was easy” because this was for the first two tasks 2.27 and 2.88 (not agree till agree). The rating for the item “the tasks support the understanding of anchoring concepts” was rated slightly better (arithmetic mean between 2.87 and 3.60). Whether the rating of these items changes should be evaluated in the near future in a course where concepts are explicitly taught and applied.

Research question 5: in what way do concepts build a bridge between university and school knowledge as defined by the SRCK-concept?

This research question takes into account that the SRCK is a knowledge category between school knowledge and university knowledge and therefore builds a bridge between those knowledge categories. SRCK-tasks should support the acquisition of this knowledge. Because the SRCK-construct included concepts, these concepts should be support this connection. The item “concepts in organic chemistry build a bridge between university and school knowledge” is rated by the students between 3.20 and 3.31 and therefore with “agree”. This also supports our claim that concepts should be an integral part of courses in organic chemistry. Student 5 says in the focus group interview: “if you had the concepts in school and you remember them at university, you could build upon them” and “if you have a concept at university, you can, because you learned it at university and because it is explicit that it is a concept, you can use it as concept in school or use it to structure lessons at school”. Student 6 supports this: “from university down to school it is supporting, because that’s the meaning of concepts to join maybe 80% of the reactions with the concepts”.

Overall, the students see the potential of concepts as forming a bridge from school knowledge to university knowledge and vice versa.