Today's schools are faced with increasingly complex demands of juggling their core educational tasks alongside multi-dimensional policy bids for reform, development and change. In this paper, we conceptualize our own RCT research on small-group tuition in mathematics in Norwegian lower elementary schools as a policy-relevant measure and part of a broader trend of evidence-based practice (EBP). Taking six of the participating schools as our empirical vantage point, we critically examine how they experience the project enactment against the broader canvas of their everyday, situated realities. Interviews with teachers and school principals show that while there is a near-unanimous agreement about the pedagogical merits of small-group tuition, enacting the RCT in practice creates multiple challenges, problems and tensions that the schools deal with in their unique ways. We argue that safeguarding local flexibility, autonomy and freedom in the face of imposed rigidity, multiple policy demands and changing circumstances are key issues to consider in planning, designing and committing to interventional research in educational policy settings.