Learning about energy is recognized as an important objective of science teaching starting from the elementary school. This creates the need for teaching simplifications that compromise the abstract nature of this concept with students' need for a satisfactory qualitative definition. Conventional teaching approaches have failed to respond to this need in a productive manner. In an attempt to maintain consistency with how energy is understood in physics, they tend to either provide abstract definitions or bypass the question "what is energy?", which is vitally important to students. In this paper, we describe the epistemological barriers that are inherent in conventional attempts to introduce energy as a physical quantity and we suggest that shifting the discussion to a philosophically-oriented context could provide a means to address them in a productive manner. We propose a teaching approach, for students in the age range 11-14, that introduces energy as an entity in a "theoretical framework" that is invented and gradually elaborated in an attempt to analyze the behavior of diverse physical systems, and especially the various changes they undergo, using a coherent perspective. This theoretical framework provides an epistemologically appropriate context that lends meaning to energy and its various features (i.e. transfer, form conversion, conservation and degradation). We argue that this philosophically informed teaching transformation provides a possible means to overcome the various shortcomings that typically characterize attempts to introduce and elaborate the construct of energy while at the same time it allows integrating, in a meaningful and coherent manner, learning objectives relevant to the understanding of the Nature of Science (NOS), which is recognized as a valuable component of learning in science. In this paper, we outline the rationale underlying this teaching approach and describe a proposed activity sequence that illustrates our proposal.