The training interventions in this dissertation fostered skill-facets and will-facets. Furthermore, they fostered argument quality referring to the output that comes from performing argumentative thinking. The training interventions also fostered self- explanation quality that referred to the central skill- and will-principles. From a more practical point of view, the goal of this dissertation was to provide instructional impli- cations for training skill and will of argumentative thinking. The following three in- structional suggestions can be derived from this research against the background of the results of all three studies. They could serve as practical implications to guide the de- sign of short-term training interventions to foster skill and will of argumentative think- ing.
3.3.1 Foster self-explanation quality that refers to central skill- and will-principles
As section 3.2.1 emphasized, it is important to ensure a high self-explanation quali- ty that refers to the central skill- and will-principles, because it was a crucial factor for learning processes during the training interventions. It mediated important effects that go beyond immediate performances (i.e., effects on declarative knowledge and epistemic knowledge after one week) and beyond effects on knowledge (i.e., effects on argument quality). How could this fostering of self-explanation quality be achieved concretely? A combination of learning goals, a theoretical introduction, and corres- ponding self-explanation prompts (all three referring to the targeted central principles) appears to be an effective way to foster self-explanation quality that refers to the central principles. This notion is not only in line with the guidelines in recent literature (e.g., Renkl, 2011, 2014), but also cross-experimentally (and thus strongly) supported by the three studies in this dissertation. After all, both the control groups and the training groups received identical video examples, thus ruling these out as a difference maker. However, only the training groups received the learning goals, the theoretical introduc- tion, and the self-explanation prompts that exclusively referred to the central skill-/will- principles. By contrast, the control groups’ learning goals, theoretical introduction, and
self-explanation prompts referred to e-learning and ecological content and neglected any principles of the skill and/or the will of argumentative thinking.
3.3.2 Foster both skill and will of argumentative thinking
When the goal is to foster argumentative thinking, learners should receive a training intervention on both the skill and the will of argumentative thinking. More specifically, such a training intervention should address the will before the skill. This implication is based on the following cross-experimental step-by-step considerations about the find- ings of all three studies and refers to the actual performance of argumentative thinking: First of all, the skill-training intervention fostered argument quality (see Study 1), which served as an indicator of argumentative thinking (see section 2.2.3). However, the skill-training intervention did not focus on the will to engage in argumentative thinking, because its goal was to exclusively foster the skill of argumentative thinking. Hence, the skill-training intervention addressed only one (i.e., the skill) of two (i.e., the skill and the will) prerequisites of argumentative thinking. Thus, with respect to argu- mentative thinking, there should be room for improvement, especially when learners with little will to engage in argumentative thinking are involved. In other words, when the goal is actually to foster argumentative thinking (and not exclusively the skill to do so) the skill-training intervention should not be the practical method of choice. The same applies for the will-training intervention. It exclusively focused on fostering the will to engage in argumentative thinking irrespective of the participants’ skill to do so. It was successful in fostering the application of evaluativist knowledge (Study 2), which can be seen as a precursor of argumentative thinking (see section 2.2.3). How- ever, this will-training intervention is not recommended when the goal is to foster ar- gumentative thinking because it did not address the necessary skill of argumentative thinking. The question arises what is the method of choice for fostering argumentative thinking? Against the background of all three studies in this dissertation, it is the com- bined-training intervention, particularly the will-skill-version. Study 3 identified the will-skill-version of the combined-training intervention—which addressed the skill after the will—as being superior at fostering argument quality when compared to the other training interventions. In a nutshell, to train argumentative thinking, it is recom- mended to foster both the skill and the will of argumentative thinking; in terms of or- der, the will before the skill for best results. As a practical implication, use the will-
skill-version of the combined-training intervention if learners should engage in argu- mentative thinking and generate their own position on conflicting scientific positions.
3.3.3 Enhance the skill-training intervention for an enduring effect on procedural knowledge
When the goal is to foster learners’ procedural knowledge about argumentation, the skill-training intervention should receive some enhancements. As section 3.1.1 pre- sents, the skill-training intervention reached its limits: Although it did indeed foster procedural knowledge immediately after the training intervention (Study 1 and Study 3), this effect was not strong enough and thus failed to show one week later in both studies. Furthermore, the combined-training intervention did not foster procedural knowledge at all (see section 2.5). This particular result was no surprise, given the modest nature of the combined-training intervention, which featured only one video example on skill. As the skill-training intervention featured two video examples on skill, it follows that one video example might not be enough to foster procedural knowledge. Therefore, from a practical point of view, an immediate effect on proce- dural knowledge requires a skill-training intervention that features at least two video examples on skill. However, as the results of Study 1 and Study 3 show, for an endur-
ing effect on procedural knowledge, a short-term skill-training intervention—even with
two video examples—is insufficient. As mentioned earlier with respect to the ACT-R theory and different knowledge types (Anderson, 1983, 1993), it might take more time and effort to acquire procedural knowledge than declarative knowledge. This is due to the fact that procedural knowledge needs to be compiled from declarative knowledge (Anderson, 1993). Now from a more practical point of view, the question arises, what modification of the skill-training intervention might foster procedural knowledge for more enduring effects?
Future studies should test a training intervention with an increased number of video examples on the skill of argumentative thinking. Study 3 showed, that one video exam- ple on skill (in the combined-training intervention) was not sufficient to produce an effect on procedural knowledge. Furthermore, Study 1 and Study 3 showed that two video examples on skill were indeed sufficient for an immediate, but in fact insufficient for an enduring effect. Even more video examples might induce an enduring effect on
procedural knowledge. Moreover, given the fact that procedural knowledge is defined as knowledge that is manifested in people’s performance (Anderson, 1993), the argu- mentation phase might play a crucial role in fostering procedural knowledge. This is due to the fact that procedural knowledge refers to knowledge about generating argu- mentative elements and the argumentation phase in fact afforded generating argumenta- tive elements for one’s own position. In other words, this phase afforded practicing just the performance that the procedural knowledge variable refers to. Thus, a further modi- fication of the skill-training intervention to improve its effectiveness on procedural knowledge might involve implementing two or more self-regulated argumentation phases. This would afford learners more occasions to practice generating their own position on conflicting scientific positions of new topics, which is likely to induce an enduring effect on procedural knowledge.