Timely assessment and feedback on classroom behavior of primary school students are important for the improvement of traditional classroom. Yet, the method mostly rely on informal oral evaluations randomly conducted in the classroom teaching process, often without clearly pre-claimed and consistent behavior expectations. This is most probably due to 1) unverified relationship between concise and context-aware classroom behavior and academic achievement and 2) the time constraint associated with various procedures inherent in regular or formative evaluation. In order to circumvent these disadvantages, we designed an iPad-based classroom behavior management system for primary school. After a serial rounds study, we concluded that this system was effective in helping improve students' academic achievement by enhancing their positive classroom behaviors.