Practical activities and green and sustainable chemistry in secondary chemistry education: teachers’ reports from Slovakia

2.1 Green and sustainable chemistry as a framework for chemistry education

Sustainability has become a central theme in science education, reflecting global concerns related to environmental degradation, climate change, and the responsible use of natural resources. International policy documents emphasise education as a key driver of sustainable development and explicitly highlight the role of science education in addressing complex sustainability challenges. ¹⁶ Within chemistry education, this shift is closely associated with the emergence of green chemistry and its broader extension into green and sustainable chemistry (GSC).

Green chemistry was originally articulated through the 12 principles proposed by Anastas and Warner ¹⁷ , which focus on waste prevention, reduced toxicity, energy efficiency, and the use of renewable feedstocks in chemical processes. In chemistry education research, this framework has been further developed into the concept of green and sustainable chemistry, which explicitly links chemical knowledge and practice to sustainability goals and the United Nations Sustainable Development Goals (SDGs). ¹⁸ From an educational perspective, GSC provides a coherent framework for connecting chemical concepts with societal decision-making, environmental responsibility, and system thinking.

Importantly, green and sustainable chemistry in education is increasingly understood not merely as the inclusion of environmentally benign reactions or safer laboratory procedures, but as a broader analytical framework for examining chemical processes in terms of their environmental, societal, and economic implications. This perspective emphasises prevention, efficiency, and informed decision-making, encouraging learners to consider alternative pathways and to reflect on trade-offs associated with chemical production and use. ^{17 , 19} As such, GSC supports sustainability-oriented reasoning and systems thinking rather than focusing solely on isolated content knowledge.

Although sustainability and green chemistry are increasingly referenced in national curricula and educational policy documents, research consistently indicates that curricular inclusion alone does not ensure meaningful classroom implementation. ^{16 , 18} . While green chemistry is widely acknowledged as an important framework for contemporary chemistry education, its systematic integration into school practice remains uneven and strongly dependent on local curricular interpretations and teacher agency, particularly with respect to how sustainability-related goals are translated into concrete teaching practices. ²⁰ Early and more recent contributions alike emphasise that GSC can be meaningfully introduced already at lower secondary level, provided that age-appropriate contexts and carefully designed learning activities are used. ^{21 ,  22}

2.2 Practical activities in chemistry education and education for sustainable development

Practical activities have long been associated with chemistry education and discussed in terms of their potential to support conceptual understanding, the development of practical skills, and scientific reasoning. ¹ More recent syntheses emphasise that the educational value of practical work depends on the meaningful integration of cognitive, procedural, and reflective components, enabling students not only to perform experiments but also to interpret results, pose questions, and reflect on their learning. ²

From the perspective of education for sustainable development (ESD), practical activities are considered a particularly important instructional approach because they can provide opportunities for students to engage with complex, real-world problems through inquiry, experimentation, and reflection. Sustainability-oriented practical work has been shown to support the development of key competencies, including critical thinking, problem-solving, and the ability to evaluate the consequences of chemical actions, provided that sustainability goals are made explicit and opportunities for reflection are embedded in the learning design. ^{23 , 24} Conceptually, this emphasis aligns with broader understandings of sustainability and sustainable development. While sustainability refers to the long-term normative vision of a sustainable world, sustainable development focuses on the pathways and processes required to achieve this vision, including the competencies needed to address present and future challenges. ²⁵ Drawing on Weinert’s conceptualization of competencies, sustainability competencies are commonly described as holistic combinations of cognitive abilities, practical skills, and motivational and social dispositions that enable individuals to respond responsibly to sustainability-related problems and to participate in shaping sustainable development across different contexts. ^{26 ,  27}

Within chemistry education, practical activities can provide authentic learning environments for the development of such competencies. Experimental work related to topics such as water quality, waste management, renewable resources, or material sustainability enables students to connect chemical concepts with real-world sustainability challenges and to engage in evidence-based reasoning. Through these activities, students are encouraged not only to observe chemical phenomena but also to critically evaluate information, ask meaningful questions, think systemically about the consequences of chemical processes, and consider alternative, more sustainable solutions. ^{24 , 28 ,  29}

2.3 Ambiguities and limitations of sustainability-oriented practical work

Despite widely acknowledged potential, practical activities are characterised by considerable pedagogical ambiguity. Research indicates that practical work does not automatically lead to conceptual understanding or higher-order thinking, particularly when activities are poorly designed or insufficiently embedded in broader learning goals. ¹³ While green and sustainable chemistry principles can be successfully translated into school laboratory activities – often through context-based or low-cost experiments aligned with curricular requirements – such approaches frequently rely on individual teacher initiative rather than systematic curricular support. ²²

Moreover, practical activities may remain limited to confirmatory demonstrations or highly structured procedures with little opportunity for inquiry, reflection, or decision-making. In such cases, practical work may illustrate concepts without fostering critical engagement with sustainability issues or supporting the development of sustainability-related competencies. Although a growing body of teaching materials illustrates the feasibility of sustainability-oriented practical work in chemistry classrooms, their presence in the literature does not necessarily indicate widespread adoption in everyday teaching practice. ^{22 ,  30}

2.4 Teachers’ perceptions and decision-making in sustainability and practical work

A growing body of research highlights the central role of teachers’ perceptions and beliefs in shaping classroom practice. Teachers’ interpretations of curricular goals influence the selection of teaching strategies, the organisation of learning activities, and the learning outcomes that are prioritised in instruction. ^{31 , 32 , 33} In chemistry education, this influence is particularly evident in relation to practical activities, which require teachers to make ongoing decisions about pedagogical purpose, student autonomy, and the allocation of instructional time.

Researchers using Q-methodology demonstrated that chemistry teachers hold qualitatively different perspectives on the purpose and value of practical activities. ³ Identified viewpoints ranged from an emphasis on experiencing chemical phenomena and confirming theoretical knowledge to a stronger focus on learning processes, inquiry, and student engagement. These perspectives were shown to shape not only the reported frequency of practical activities but also the degree of student autonomy and the pedagogical intentions underlying practical work.

Comparable variability has been documented in research on teachers’ perceptions of sustainability and the SDGs. Studies suggest that teachers often simplify sustainability-related content in order to enhance perceived comprehensibility, which may result in selective treatment of sustainable development in classroom practice. ¹² Different educational traditions of sustainability education have been described, including fact-oriented approaches focusing primarily on ecological issues, normative approaches emphasising values and lifestyle choices, and pluralistic approaches that frame sustainable development as a moral and political issue requiring critical discussion and deliberation. ¹¹ Empirical studies further indicate that teachers differ considerably in how they conceptualise sustainability, ranging from limited or fragmented understandings to more multidimensional perspectives aligned with the SDGs. ¹⁰

Consistent with these findings, Kotuľáková, Kohutiarová, Orolínová and Trčková identified differentiated perspectives among Slovak and Czech secondary school teachers, characterised by selective prioritisation of SDG features. ⁶ While some perspectives emphasised education and social justice, others focused on specific SDGs or local action, with environmental aspects not being uniformly prioritised across viewpoints. Such selective understandings of sustainability are likely to influence how teachers perceive the relevance, feasibility, and pedagogical value of green and sustainable chemistry topics, particularly when these require modifications to established laboratory practices.

2.5 Sustainability in curricula and the implementation gap

Despite the increasing prominence of sustainability and green chemistry in curricular frameworks, a growing body of research points to a persistent gap between declared curricular intentions and classroom implementation. While sustainability is widely recognised as an important educational goal, policy documents often provide limited guidance on how sustainability concepts should be enacted through chemistry teaching and, in particular, through practical activities. ¹⁶

In the Slovak chemistry curricula at both lower secondary (ISCED 2) and upper secondary levels (ISCED 3), topics related to environmental protection, resource use, and human impacts on the environment are explicitly included, even though the term green chemistry is not used. ³⁴ Sustainability-related content is embedded across several thematic areas, including water quality, air pollution, waste management, energy resources, and the environmental and health impacts of chemical substances. These themes provide natural entry points for addressing principles aligned with green and sustainable chemistry through practical activities. However, explicit guidance on how these topics should be systematically implemented through sustainability-oriented practical work remains limited. Similar patterns have been reported internationally, where green and sustainable chemistry is often acknowledged at the curricular or policy level but implemented primarily through isolated examples rather than as a coherent pedagogical framework. ^{19 ,  35}

Empirical research further suggests that teachers tend to prioritise selected aspects of sustainability, most commonly environmental protection, while social, economic, and systems-oriented dimensions receive less attention. ¹⁰ Research also demonstrated substantial variation in how teachers conceptualise and prioritise sustainability goals, with these differences shaping instructional decisions and classroom practices. ⁶ Taken together, these findings highlight a persistent implementation gap between curricular intentions and everyday classroom practice.

2.6 The global IUPAC GASC teacher survey and contribution of the present study

In response to the research gap identified in the literature, the International Union of Pure and Applied Chemistry (IUPAC) initiated the Global Teacher Survey on Green and Sustainable Chemistry (GASC) Practical Activities. The survey was designed to establish a baseline understanding of how chemistry teachers worldwide report using practical activities and the extent to which these activities are perceived to incorporate principles of green and sustainable chemistry. ³⁶

Building on this international framework, the present study focuses on data collected from chemistry teachers in Slovakia. By analysing teachers’ self-reported classroom practices, perceived influencing factors, and reported barriers, the study provides empirical insight into how GSC is described and perceived to be integrated into practical activities at the national level. At the same time, the use of a common international survey instrument enables the Slovak findings to be situated within a broader global context.

The present study contributes to the literature by providing empirical evidence on how chemistry teachers report using practical activities and how these activities are perceived to relate to GSC, by identifying factors and constraints shaping instructional decision-making, and by contributing national-level data to an international research framework.

Accordingly, the study is guided by the following research questions:

1. How do chemistry teachers in Slovakia report using practical activities in their lessons in terms of type and frequency?

2. Which pedagogical, conceptual, and contextual factors do chemistry teachers in Slovakia perceive as influencing their selection of practical activities, including those related to green and sustainable chemistry?

3. What barriers do chemistry teachers in Slovakia perceive as limiting the more frequent or more diverse use of practical activities, including sustainability-oriented practical work?

4. To what extent do chemistry teachers in Slovakia report integrating green and sustainable chemistry topics into practical activities, and which areas of green and sustainable chemistry are perceived as emphasised or underrepresented?

3.1 Research design

This study employed a quantitative survey research design with supplementary qualitative elements, drawing on data collected as part of a large international project investigating chemistry teachers’ use of practical activities related to green and sustainable chemistry. The present paper reports a secondary, country-specific analysis of data collected from in-service chemistry teachers in Slovakia.

The research design was descriptive and exploratory in nature. The study aimed to document teachers’ self-reported classroom practices, perceptions, and perceived constraints related to practical work and the integration of green and sustainable chemistry (GSC). It did not seek to evaluate instructional effectiveness or to establish causal relationships between variables.

The study was conducted within the framework of the IUPAC-funded Global Green and Sustainable Chemistry (GASC) Teacher Survey. The development, validation, and international implementation of the survey instrument are described in detail by Delaney, Chiavaroli, Dissanayake, Pham and Schultz. ³⁶ The Slovak dataset enables a more detailed examination of national patterns and their interpretation within a specific educational and curricular context.

3.2 Research tool

Data were collected using an online questionnaire developed collaboratively by an international research team and administered via the Qualtrics platform. The questionnaire was translated into Slovak following a standard translation and review procedure coordinated by the international project team to ensure conceptual equivalence.

The questionnaire consisted of several thematic blocks:

1. demographic and professional background information, including teaching experience, and school context;

2. frequency of practical activities, measuring how often different types of activities (e.g., student-performed experiments, teacher demonstrations, videos, simulations, data analysis tasks) were used in chemistry lessons;

3. factors influencing the selection of practical activities, focusing on perceived importance of conceptual, pedagogical, motivational, and logistical considerations;

4. perceived barriers to practical work, such as time constraints, access to resources, laboratory availability, and curriculum-related limitations;

5. green and sustainable chemistry, including teachers’ estimates of the proportion of their practical activities related to GSC, factors influencing the selection of GSC activities, sources of inspiration, and open-ended descriptions of examples of GSC-related practical activities;

6. country-specific items included in the Slovak version of the questionnaire, addressing pre-service teacher preparation in green and sustainable chemistry and teachers’ goals for GSC-related activities.

Most items employed five-point Likert-type response scales. In addition, several open-ended questions allowed respondents to elaborate on their practices, provide illustrative examples, and identify challenges not fully captured by closed-response items.

3.3 Participants and data collection

The target population consisted of in-service chemistry teachers working at lower secondary level (ISCED 2; students aged approximately 11–15), upper secondary level (ISCED 3; students aged approximately 16–19), and eight-year secondary schools (selective academic secondary schools enrolling students from approximately age 11) in Slovakia (Figure 1).

Figure 1:

Number of participating chemistry teachers by school type.

The study employed a national voluntary response survey design. Invitations were distributed via email through professional mailing lists. A total of 364 chemistry teachers participated, representing approximately 18 % of schools offering chemistry education nationwide. Although the sample was not probability-based, the distribution of respondents across regions, school types, and urbanicity broadly reflected national statistics, suggesting coverage across key structural characteristics. Nevertheless, because participation was voluntary, the findings should be interpreted as descriptive and may be subject to self-selection bias.

Most respondents held a master’s degree in chemistry or chemistry education, and teaching experience ranged from novice teachers to those with more than 30 years of practice.

3.4 Data analysis

Quantitative data were analysed using descriptive statistical methods. Frequencies, percentages, and measures of central tendency were calculated to describe teachers’ reported practices, perceived importance of selection criteria, perceived barriers, and reported integration of green and sustainable chemistry. Teaching experience was measured using a categorical self-report item. Responses to open-ended questions were analysed using a descriptive, inductive qualitative approach. Teachers’ responses were reviewed and grouped into thematic categories to identify commonly reported types of green and sustainable chemistry activities, recurring challenges, and perceived needs. Selected responses were used as illustrative examples to complement and contextualise the quantitative findings, rather than to generate independent qualitative claims.

3.5 Ethical considerations

The study adhered to ethical standards for educational research. Participation was voluntary, and respondents were informed about the purpose of the study and the anonymous handling of their data. No personally identifiable information was collected. Data were stored securely and used exclusively for research purposes.

4.1 Types and frequency of practical activities reported by chemistry teachers

Teachers were asked to indicate how frequently they implemented different types of practical activities in their chemistry lessons. These activities differed in the level of student involvement and included student-performed experiments, teacher demonstrations, videos, animations, computer simulations, and student work with experimental or secondary data (Figure 2).

Figure 2:

Teachers’ reported frequency of different types of practical activities. (1) More than once, (2) around once per week, (3) around once per month, (4) a few times per year, (5) never.

Overall, the results indicate that teacher-led demonstrations were the most frequently used form of practical activity. Nearly half of the respondents reported demonstrating chemical reactions or experiments at least once per week. Similarly, showing models or visual representations of chemical phenomena was reported as a common instructional practice.

Student-performed experiments were also relatively common, although less frequent than demonstrations. Approximately one third of teachers reported that all students carried out experiments about once per month, while slightly more than one fifth reported conducting student experiments on a weekly basis. However, a notable proportion of respondents indicated that student experiments were implemented only a few times per year.

In contrast, digital forms of practical engagement were used considerably less often. Computer-based simulations and student-led data analysis tasks were among the least frequently reported activities. Approximately two thirds of teachers indicated that they never or only very rarely used simulations of chemical processes or provided students with experimental or secondary datasets for analysis. Videos and animations were used more frequently than interactive simulations but still less often than hands-on activities. Teachers reported using videos of chemical experiments or reactions primarily as supplementary resources rather than as substitutes for practical work conducted by students.

Taken together, these findings suggest that chemistry practical work in Slovak classrooms is characterized by a predominance of teacher-centred demonstrations, complemented by occasional student-performed experiments, while opportunities for student-led inquiry, data analysis, and digital simulation remain limited.

4.2 Perceived factors influencing the selection of practical activities

Teachers were asked to rate the importance of various factors when selecting practical activities for their chemistry lessons. These factors reflected pedagogical aims, student engagement, skill development, and practical constraints (Figure 3).

Figure 3:

The importance of each of the following factors for teachers when choosing chemistry practical activities. (1) Not at all important, (2) slightly important, (3) moderately important, (4) very important, (5) extremely important.

The results show that pedagogical considerations related to student learning were rated as the most important factors overall. The highest levels of importance were assigned to activities that support students’ conceptual understanding and enable them to link their observations to the current curriculum topic. A large majority of respondents rated this factor as very important or most important.

Similarly, factors associated with the development of students’ transferable skills were rated highly. Teachers placed strong emphasis on practical activities that allow students to develop critical thinking and problem-solving skills, as well as opportunities for teamwork. Activities that support the acquisition of chemistry-specific practical skills, such as weighing, pipetting, or titration, were also considered important by most respondents.

Factors related to student motivation and classroom engagement were ranked slightly lower but still received high importance ratings. Many teachers indicated that students’ enjoyment of practical activities and improved student behaviour during practical work were relevant considerations when choosing an activity.

In contrast, factors associated with practical feasibility and teacher workload showed a more mixed pattern. While safety was consistently rated as an important or very important criterion, other feasibility-related factors, such as ease of preparation or the likelihood that an experiment would always produce the “correct” result, were rated as less critical overall. Nonetheless, these factors were still considered important by a substantial proportion of teachers.

Overall, the findings indicate that Slovak chemistry teachers prioritise educational value and skill development when selecting practical activities, while considerations related to feasibility and workload, although relevant, play a secondary role in decision-making.

4.3 Perceived barriers limiting the use of practical activities

Teachers were asked to identify factors that prevent them from using practical activities more frequently in their chemistry lessons. Multiple barriers could be selected, allowing respondents to reflect the complexity of constraints they experience in practice (Figure 4).

Figure 4:

Reported factors limiting more frequent use of chemistry practical activities, grouped by category.

The most frequently reported barrier was lack of time during lessons. Approximately two thirds of respondents indicated that limited lesson time prevents them from implementing practical activities more often. Material and infrastructural constraints were also commonly identified. Many teachers reported limited access to laboratory facilities, particularly in schools where chemistry laboratories are shared or not available. Lack of resources, including chemicals, equipment, and funds for consumables or waste disposal, was another frequently cited barrier.

Curriculum-related constraints were reported less frequently but were still relevant for a considerable number of respondents. Some teachers indicated that curricular pressure and the amount of prescribed content limited opportunities for practical work, particularly when preparing students for examinations.

In contrast, personal or pedagogical factors were rarely identified as major barriers. Only a small proportion of teachers indicated lack of confidence, insufficient pedagogical knowledge, or uncertainty about how to conduct practical activities as significant obstacles. Similarly, concerns related to classroom management during practical work were reported infrequently.

Overall, the results indicate that barriers to practical activities teachers perceive are predominantly structural and organisational in nature, rather than related to teachers’ professional competence or willingness to use practical work in chemistry teaching.

4.4 Reported integration of green and sustainable chemistry in practical activities

4.4.1 Extent of reported integration of GSC topics

Teachers were asked to estimate the proportion of their chemistry practical activities that are related to green and sustainable chemistry (GSC). Responses indicate considerable variation in the reported level of integration (Figure 5).

Figure 5:

Chemistry practical activities teachers claim involve green chemistry or relate chemistry to sustainability.

The largest group of respondents reported that GSC-related topics account for a relatively small proportion of their practical activities. Approximately two-fifths of teachers indicated that green and sustainable chemistry constitutes 0–20 % of their chemistry practical work. A comparable proportion of respondents reported a moderate level of integration, estimating that 21–60 % of their practical activities are related to GSC. Only a minority of teachers reported a high level of integration, with more than 60 % of their practical activities focusing on green and sustainable chemistry. The median response corresponded to approximately 30 % of practical activities, suggesting that while GSC topics are present in chemistry teaching, they are not a dominant component of practical work for most teachers.

4.4.3 Sources of inspiration for GSC-related practical activities

Teachers were asked to evaluate which factors influence their selection of green and sustainable chemistry (GSC) practical activities and to indicate the sources they use when developing or adopting such activities (Figure 6).

Figure 6:

The claimed importance of factors when choosing GSE practical activities. (1) Not at all important, (2) slightly important, (3) moderately important, (4) very important, (5) extremely important.

When selecting GSC-related practical activities, teachers reported patterns that were similar to, but not identical with, those observed for practical activities in general. Pedagogical considerations again received the highest importance ratings. Teachers most strongly valued GSC activities that help students understand the relevance of chemistry to real-world environmental issues and that support students’ conceptual understanding of sustainability-related concepts. Factors related to student engagement and motivation were also rated as important in the context of GSC. Many teachers indicated that they prioritise activities that connect to students’ everyday experiences or local environmental issues. In addition, the potential of GSC activities to foster critical thinking and discussion about environmental challenges was rated highly. The highly ranked factor influencing green chemistry practical activities in chemistry lessons relates to transferable skills.

Practical and logistical considerations played a more prominent role in the selection of GSC activities than in the selection of practical activities overall. Availability of suitable materials, safety considerations, and ease of implementation were frequently rated as important or very important factors. Teachers also indicated that aligning GSC activities with the existing curriculum was an important consideration.

4.4.4 Differences by teaching experience

When the reported reasons for selecting green and sustainable chemistry topics were examined across groups defined by length of teaching experience, broadly similar patterns were observed across all groups. All four reasons were rated as important by teachers regardless of experience. However, some differences in emphasis were evident. Teachers with shorter teaching experience tended to assign higher importance to the use of practical activities as a hands-on way to introduce green chemistry and sustainability, whereas teachers with longer experience more frequently emphasised opportunities for developing students’ critical thinking and problem-solving skills related to green and sustainable chemistry (Figure 7).

Figure 7:

Differences in teachers’ reported reasons for selecting green and sustainable chemistry topics by length of teaching experience.

Teachers reported using a variety of sources when developing or adopting GSC-related practical activities. Informal sources, such as self-designed activities, online resources, and materials shared by colleagues, were the most reported. Formal sources, including pre-service teacher education, in-service professional development courses, and academic publications, were reported less frequently as sources of inspiration for GSC activities (Figure 8).

Figure 8:

Sources of GSC–related practical activities reported by teachers.

Overall, the results suggest that while Slovak chemistry teachers draw on similar pedagogical criteria when selecting both general and GSC-related practical activities, the implementation of GSC is more strongly shaped by practical constraints and relies heavily on teachers’ individual initiative and informal professional networks.