“…Sixty-six leadership practices were recognized, incorporated into 21 leadership responsibilities, each with a statistically significant correlation with student achievement (Waters et al, 2004). Cross-thematic integration in teaching is a concept that entails linking different subjects between different fields or linking different subjects within the same field (Papaioannou, Milosis, & Gotzaridis, 2019;Savelides, Fasouraki, Georgousis, Kolokotroni, & Savelidi, 2020). A cross-thematic curriculum does not only constitute a significant change in the organization and delivery of various courses, but it represents a different way of using knowledge to solve real-life problems (Al Salami, Makela, & de Miranda, 2017;Gosselin, Manduca, Bralower, & Egger, 2019;Karppinen, Kallunki, & Komulainen, 2019).…”