This paper presents a pedagogical experiment with parallel groups through which the effectiveness of the cognitive apprenticeship model of dealing with the teaching topic Carboxylic acids and their derivatives was compared with the traditional approach to the elaboration of this topic. This experiment featured the participation of 241 students aged 17, attending their third year of grammar school, natural sciences stream. The experimental group consisted of 118 students, whereas the control group was made up of 123 students. Within the framework of the experiment, a pre-test consisting of items that resembled regular textbook items was used as an instrument for checking how balanced the previously acquired knowledge concerning the teaching topic Carboxylic acids and their derivatives of the students in the two groups was. A post-test was used as an instrument for comparing the effectiveness of the two approaches, and it mostly consisted of items that required the application of the knowledge concerning the teaching topic Carboxylic acids and their derivatives in solving real-life problems. In the pre-test, no statistically significant difference in the overall percentage of correct answers given by the two groups of students was established. In the post-test, the students from the experimental group scored a statistically significant higher percentage of correct answers compared to the students from the control group. On the basis of this, it can be concluded that the applied cognitive apprenticeship approach has the potential to improve the level of students’ understanding of the concepts from the topic Carboxylic acids and their derivatives, as well as the students’ ability to apply the knowledge on the examples from real life.

Previous studies noted the scantiness of diagnostic instruments for the assessment of students’ understanding of fundamental biochemistry concepts. Consequently, within this study, a four-tier test for the examination of secondary school students’ conceptual understanding of amino acids, proteins, and enzymes has been developed. Items in the test consist of the answer tier, the reason tier, and a confidence rating for each of these tiers. Following the three-phase development process, the final version of the test, comprising eight items, was administered to 123 students in the main study. The internal consistency of both cognitive scores and confidence ratings proved to be adequate (Cronbach’s alpha values were 0.76 and 0.87, respectively) and the test–retest reliability was also satisfactory (Pearson’s r value was 0.74 for the cognitive scores and 0.88 for the confidence ratings). If the correct responses to both the answer and the reason tier of items are considered, the mean score on the test was 3 out of 8 (38%). The students were more confident when producing the correct compared to the wrong answers but, overall, their confidence was not high (3.65 out of 6). Furthermore, the confidence in the incorrect answers that were provided (3.52 out of 6) indicates the presence of alternative conceptions. Such results show that the content regarding amino acids, proteins, and enzymes is conceptually challenging for the students. Therefore, the test can help secondary school teachers to uncover the students’ conceptual difficulties related to this content and develop effective strategies for their remediation and prevention. Supplementary Information The online version contains supplementary material available at 10.1007/s11165-022-10075-5.

Adolescents are considered as a nutritionally vulnerable subgroup because of their alimentary behaviours. Considering that alimentary habits are strongly influenced by knowledge about digestion, an experiment was conducted with aim to determine whether conceptual understanding and functionalization of this knowledge can be improved by the interdisciplinary teaching approach. The experiment encompassed 258 students attending the fourth year of high school. No statistically significant difference in the level of the previously acquired chemistry, biology and physics knowledge concerning digestion between the two groups was determined on the pre-test. Conversely, the students in the experimental group significantly outperformed those in the control group on the post-test that required a deep understanding and the application of knowledge about digestion in solving real-life problems. Therefore, it was concluded that high- school teachers can be advised to apply the interdisciplinary teaching approach in order to improve their students' knowledge about this process. Key words: conceptual understanding, process of digestion, functionalization of acquired knowledge, interdisciplinary teaching approach.

Organic chemistry represents an essential part of everyday life, but previous research indicates that traditional organic chemistry teaching, which focuses on the transmission of academic content, insufficiently promotes the development of pupils' chemical literacy in this field. Since context-based teaching approach has the potential to improve scientific literacy, in order to compare the effectiveness of the aforementioned teaching approaches in terms of developing elementary school pupils' chemical literacy in the field of organic chemistry, a pedagogical experiment with parallel groups was conducted. The experiment was organized within the elaboration of the teaching unit Alkanes and it encompassed 148 eighth-grade elementary school pupils (76 pupils in the experimental and 72 pupils in the control group). Through the elaboration of the content about alkanes, pupils develop chemical literacy in regard to the structure and nomenclature of these compounds, their physical and chemical properties and oil and its derivatives as energy sources, as well as environmental pollutants. Upon the elaboration of the abovementioned teaching unit, the experimental group achieved a significantly higher overall percentage of correct answers on the test that checked the development of pupils' chemical literacy in regard to alkanes on all three levels (knowledge, application and reasoning), which implies that context-based teaching approach could significantly enhance elementary school pupils' chemical literacy, in the field of organic chemistry.

This cross-age study aimed to provide an insight into the development of stu- dents’ understanding of the concept of matter, at the macroscopic and sub-microscopic level of chemistry knowledge. The research sample encompassed 121 students aged 14 years, 108 stu- dents aged 16 years and 112 students aged 19 years. All students completed the test comprised of five pictures and five schemata which depicted a monatomic/diatomic element, a compound and a homogeneous/heterogeneous mixture, at both of the levels. In this way, it was examined whether the selected age groups exhibit significant differences in understanding of elements, compounds and mixtures at the above-mentioned levels and whether the depth of understanding of these concepts at the macroscopic and sub-microscopic level significantly changes with the age of students. Research results indicate that all three age groups have a significantly better understanding of diatomic elements, compounds and heterogeneous mixtures at the macro- scopic, in comparison to the sub-microscopic level and a significantly better understanding of monatomic elements and homogeneous mixtures at the sub-microscopic, in comparison to the macroscopic level. Overall, a significant improvement of understanding of the concept of matter, at each of the levels, was only observed between the ages of 14 and 16.