Ben van der Hilst

344 king, learning and the further development of education come together in the work of the education teams and expert teams (departments). Building blocks of the TOS concern the size of the teams, responsibilities, powers and certain institutional rules. The TOS seems to fill the gap currently existing in the management repertoire of school leaders. The developed practice-based the- ory is, however, strongly linked to the person of the author and has only been tested in a limited number of situations. Therefore, further research is needed to fulfill the ambition of providing a more general and validated tool for school leaders, as well as to further develop the theory of school leadership. Method After exploring a number of research approaches, the choice was made to use the TOS as a starting point for design-oriented scientific research. This type of research focuses on solving a practical problem while at the same time producing general knowledge. In design-oriented research a possible solution to the practical problem, in this case the TOS, is tested in certain contexts to see whether the design leads to the envisaged outcomes. This also offers the opportunity to investigate why the organization model works and how the model can be further improved and enri- ched. In addition, testing the model in other schools with school leaders other than the researcher himself also provides an opportunity to study the reception of the model by school leaders, which in turn provides information about the usability of the tool and how the organization model can best be presented. The problem formulation in design-oriented scientific research is contained in a design theorem or design rule. The theorem for this research is: In schools characterized by weak connections between the different actors (teachers, teams, management), the introduction of the TOS strengthens the connections between them in such a way that the likelihood of a higher quality of education, greater agility of the organization and more job satis- faction for the employees is increased. In order to validate this theorem, the concepts of educational quality and agility need to be further explored. The concept of educational quality is highly dependent on the professional behavior of the teacher during the educational process. In this study, this professional behavior is referred to as type 1. It includes pedagogical, didactic and subject related behavior. Increasing the quality of this type of behavior also requires professional action of the teacher “outside the classroom”.