Ontologies enable learning objects sharing and reuse in a contextual learning environment and provide better search and navigation of learning objects. Ontologies add semantics to content components, which provide context to learning objects. This paper presents the use of Formal Concept Analysis (FCA) to structure knowledge ontologically and the Self-Organizing Map (SOM) to reduce the problem size. To gain better visualization of the intrinsic relationship between ontological concepts, k-means clustering is applied on the clustered SOM.