An interactive chart of energy metabolism with didactic function, complementary to the already existing metabolic maps, located at the URL www.metpath.teithe.gr is being presented. The chart illustrates the major catabolic and biosynthetic pathways of glucose, fatty acids, and aminoacids, individually as well as in an integrated view. For every metabolite and reaction an information sheet may be presented at the side of the map as fancybox, containing chemical structural formulae, an external link to the KEGG database and links that lead to the reactions at which the produced metabolites may participate as reactants. The latter allows the user to navigate through metabolic reactions following a route similar to the metabolic flow of substances, while keeping track of the occurring chemical transformations. Simultaneously, users may observe how they move across the metabolic map, possibly along different pathways, thus enhancing the user's integrated perception of metabolism. The site has already been introduced in biochemistry lectures and the students evaluated it. Most students were helped a lot or more to understand individual pathways as well as their interconnections and they also found it pleasant and easy to navigate. The vast majority of the students considered its use in the classroom desired. The chart currently may be displayed in English and in Greek while more languages can be integrated in the future. The authors' view, in accordance to the users' perception, is that the presented site may offer biochemistry tutors and students a useful teaching aid.