Data mining is an innovative approach for teaching and learning process in education. National Board of Accreditation (NBA) is outcome based learning education. Faculty has to measure and assess the CO and PO attainment with respect to a number of direct and indirect tools, where a lot of clerical errands get involved. The assessment may get troubled due to the time constraints and various other activities. There is no such active system which will reduce these efforts. Our tool atomizes it. Through the Knowledge based tool for PO attainment we can reduce the intricacy in PO attainment process of NBA. Mainly the Knowledge based tool is used to reduce the clerical work of faculty in the assessment. In the given system classification algorithm and Bloom’s taxonomy is used in mapping COs with POs .This system helps us to appraise mapping between COs and POs for each subject with the help of direct and indirect measures.