Helping students to develop their ability to think is a commonly stated goal in educational statements worldwide. This has also become a significant objective in the curriculum reforms in Hong Kong, which aims at better preparation of our students to meet the challenges of the new era. The paper discusses findings from a study which evaluates how a school implemented a thinking curriculum. The findings inform the research area of higher-order thinking (HOT) teaching. To evaluate the degree of implementation of the HOT curriculum in the school, the technique of Innovation Configuration Mapping (IC Mapping) was used. This study pioneers the instrument as a way to understand how HOT is taught in classrooms. Findings from the study confirm that IC Mapping is a useful diagnostic procedure for assessing the implementation of an innovation. By figuring out the IC Maps of the case school, the ideal form of HOT is further defined. It is found that the more ideal HOT teaching is not only a technical matter; it requires something more fundamental than knowledge or skills. The research findings show that there was disparity among teachers when they put the collaborative planning into actual implementation in classrooms. Findings suggest that teaching of thinking requires a change of paradigm and beliefs about teaching. The article infers that a misalignment between the desire for change in curriculum aims and the demands of assessment is a common and dominant barrier for innovation in many places and countries. Finally the author proposes that teaching of HOT is salient for democratic development of a community.