Education for environmental sustainability has emerged as a critical global priority in response to escalating ecological challenges such as climate change, biodiversity loss, and resource depletion (UNESCO, 2020). Schools have a central role in advancing sustainability education, acting as arenas where knowledge and values are translated into behaviors and actions  (Campfens, 2024). Teachers are key agents in this process, responsible for embedding the sustainability principles described in the curricula into the classrooms and fostering competencies such as critical thinking, action competence, and lifelong learning among students (Felix et al., 2025; Zarzycki, 2025). Students, in turn, are expected to develop not only cognitive understanding but also behavioral dispositions that support sustainable lifestyles (Ardoin et al., 2020).

The Nordic countries are recognized as leaders in environmental sustainability education (Kardyb et al., 2025; Nordic Council of Ministers, 2024). Across Finland, Norway, and Sweden, sustainability is embedded in national curricula and governance documents, reflecting shared commitments to the United Nations Sustainable Development Goals (United Nations, 2015) as well as international frameworks such as UNESCO’s Education for Sustainable Development roadmap (UNESCO, 2020) and the UNECE Strategy for Education for Sustainable Development (UNESCO, 2022). Despite these common policy orientations, the countries differ in pedagogical traditions and implementation strategies. Sweden has a long-standing emphasis on outdoor and experiential learning, Norway foregrounds democratic participation and interdisciplinary approaches, and Finland integrates sustainability through phenomenon-based learning and whole-school models (Kardyb et al., 2025; Nordic Council of Ministers, 2024).

The Trends in International Mathematics and Science Study (TIMSS) incorporates environmental modules designed to capture key dimensions of students’ environmental awareness at the international level (Bookbinder et al., 2025). This approach is consistent with widely used conceptualizations of environmental awareness, which typically encompass students’ knowledge of environmental issues, their attitudes and values related to sustainability, and their reported behaviors or behavioral intentions (Bookbinder et al., 2025; Firmanshah et al., 2023). Informed by the Model of Ecological Values (Bogner & Wiseman, 2006) and the Theory of Ecological Attitude (Kaiser et al., 1999) the TIMSS framework operationalizes environmental awareness primarily through students’ environmental values and self-reported behaviors (Reynolds & Komakhidze, 2022).

To guide the present analysis, we adapted the dynamic model of educational effectiveness (DMEE) (Kyriakides & Creemers, 2009) to develop an environmental sustainability education framework.  This adaptation focuses specifically on environmental sustainability in schools and operationalizes its multilevel structure by linking national-, school-, and classroom-level actions in sustainability education to student outcomes, such as environmentally responsible behaviors. Consistent with the DMEE, the framework assumes that environmentally responsible behaviors emerge from interactions across multiple levels of the education system.

Through the proposed framework and given the novelty and policy relevance of the environmental sustainability scales in TIMSS, this study examines cross-national differences among the Nordic countries in school emphasis on environmental sustainability, teacher emphasis on environmental sustainability, and student environmental awareness. The primary focus is on evaluating the factorial structure and cross-country comparability of these constructs.

Thus, the research questions (RQ) are:

1)      To what extent do Nordic countries differ with respect to environmental awareness?

1. To what extent do Nordic countries differ with respect to school emphasis on environmental sustainability?
2. To what extent do Nordic countries differ with respect to teacher emphasis on environmental sustainability?
3. To what extent do Nordic countries differ with respect to students’ environmental awareness?

This study used secondary data from TIMSS 2023. TIMSS is conducted every four years and assesses student achievement in mathematics and science at the fourth and eighth grade levels, providing trend data across participating countries (von Davier et al., 2024). Schools are first selected using probability proportional to size sampling, followed by the random selection of one or two intact classrooms within each school. The present analyses included Grade 8 data from Finland including 5880 students, 395 classes, and 161 schools, Norway including 6324 students, 298 classes, and 157 schools, and Sweden 5080 students, 240 classes and 154 schools. Due to differences in school entry age with respect to other Nordic countries, Norway administers TIMSS to students in Grades 5 and 9. Sampling weights were applied at the student, teacher, and school levels to ensure that the sample is representative of students in each country. All measures were derived from the TIMSS 2023 contextual questionnaires and were operationalized in accordance with the original TIMSS scale definitions. Student-reported measures included three latent variables: student value environmental preservation, student value environmental utilization, and environmentally responsible behaviors. The environmental preservation scale consisted of six items, and the environmental utilization scale consisted of three items, all rated on Likert-type agreement scales. The environmentally responsible behaviors scale included six items measuring the frequency of students’ self-reported pro-environmental actions. Teacher-reported measures comprised two latent variables including teacher emphasis on environmental sustainability and teacher actions to teach environmental sustainability. Each latent variable was measured using four items reflecting instructional emphasis and pedagogical practices related to environmental sustainability. All teacher items were rated on ordinal Likert-type scales indicating frequency or degree of emphasis. Principal-reported measures included a single latent variable, school emphasis on environmental sustainability, measured using eight items capturing school-level priorities, practices, and organizational support for environmental sustainability. Items were rated on Likert-type agreement scales. Data were prepared in R version 4.5.2, and analyses were conducted in Mplus 8.11 (Muthen & Muthen, 2017; R Core Team, 2021). Given the ordinal nature of the indicators, models were estimated using the weighted least squares mean and variance adjusted estimator. First, confirmatory factor analyses (CFA) were conducted separately for each country to evaluate the hypothesized factor structures. Second, multi-group CFA was used to examine measurement invariance across countries. When full scalar invariance was not supported, partial scalar invariance was established by freeing theoretically justified item thresholds

Overall, the results provide initial empirical support for the proposed framework of environmental sustainability in education. Across the Nordic countries, most student-, teacher-, and school-level constructs demonstrated acceptable model fit, reliability, and at least metric levels of measurement invariance, indicating that the key dimensions of environmental sustainability captured by the TIMSS scales are largely comparable across national contexts. Specifically, student-related constructs showed strong psychometric properties and higher levels of invariance, allowing for meaningful cross-national comparisons of latent means for most constructs (environmentally responsible behaviors and students value environmental preservation). At the school and teacher levels, the need for scale modifications and the lower reliability observed for some constructs (school emphasis on environmental sustainability and teacher actions) suggest greater contextual variation in how environmental sustainability is operationalized at these levels. Nonetheless, the achievement of metric or partial scalar invariance supports the use of these measures for comparing country level means and further examining structural relations within the proposed framework. Taken together, these findings indicate that the proposed framework is reasonable venue for structuring and organizing multilevel aspects of environmental sustainability in education, while also highlighting areas where further scale development and refinement are needed. Subsequent analyses will extend the measurement models by estimating structural relations, examining how school-, teacher-, and student-level aspects of environmental sustainability predict environmentally responsible behaviors

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