This paper reports the implementation results of the Portuguese School Libraries Evaluation Model, more specifically the results of primary schools self-evaluation of their libraries' reading promotion and information literacy development activities. School libraries that rated their performance as either "Excellent" or "Poor" have been purposefully selected as case studies. Following a QUAN-QUAL approach to data collection and analysis, we first present the results of two surveys designed respectively to understand how students relate to reading and information access, production and communication in the context of the school library provision, and to map teachers' perceptions on school libraries' systematic promotion of reading and information literacy. In the qualitative component of the study, the evaluation reports submitted by school libraries were subject to thematic analysis to unearth meanings assigned and core concepts employed to classify school libraries' provision. The thematic analysis of reports was also used to further confirm the validity of schools' self-attributed performance levels. The paper calls for the development of an evaluation culture in school libraries, and suggests the development of an online case repository, which would operate as evaluation's interface with new organisational practices. (Contains 8 tables and 1 figure.)