Despite acknowledgement in the data-informed decision making (DIDM) literature that data use is not a purely rational process, there has been little attention paid to the role of values and normative factors that underpin school improvement planning (SIP) processes and little consideration of the inherent evaluative nature of associated activities in K-12 educational contexts. Through interviews, observations, and the review of documentation related to SIP activities, this multiple case study explores data use practices and evaluative thinking within the context of two, Title I, targeted support and improvement (TSI) elementary schools in a single district in North Carolina. The findings suggest that SIP processes in these contexts are shaped by social and historical factors as well as the leadership philosophies and practices of principals. The findings also provide insight into how school SIP teams adapt current institutional policies and mandates as well as data tools and existing data infrastructures to balance adherence to requirements and for addressing local needs. Implications of this study are discussed in relation to the modernist orientations of evaluation that emerged in these SIP contexts. In subtle but important ways, this orientation narrows the focus of SIP teams to technical and rational understandings of what are ultimately complex social and political problems. Furthermore, the discussion highlights how this orientation to SIP processes limit opportunities for local educators to engage in evaluative thinking and critical reflection to promote nuances and rich understandings of local contexts, as well as more complete and balanced understandings of the impacts of SIP strategies or initiatives that are implemented. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]