1. A computer-implemented method of problem solving comprising: accessing, with a computer, stored data representing a first concept map, wherein the first concept map includes a plurality of nodes and a plurality of paths that connect the plurality of nodes, wherein each one of the plurality of nodes has at least one equation for solving a problem using a plurality of variables, wherein the plurality of variables are associated with one or more other nodes of the first concept map, wherein the plurality of paths that connect the nodes depict the relationships that exist between the variables of the equations of the respective nodes, and wherein the plurality of variables include scalar variables and vector variables; graphically displaying, by the computer, a plurality of concepts by displaying the nodes of the first concept map and the plurality of paths that connect the nodes; receiving user input, into the computer, that specifies one of the nodes; displaying, by the computer, the at least one equation of the specified node; receiving further user input for the specified node, into the computer, that specifies input values for variables of the at least one equation of the specified node that are known variables and that selects at least one variable as an unknown variable of the at least one equation of the specified node; selectively displaying by the computer, based on the specified node of the received user input and the specified values of known variables and the at least one unknown variable of the at least one equation of the specified node, and distinguishing at least a first path of the plurality of paths through the plurality of the nodes of the first concept map, wherein the first path can be used to solve the problem and when a plurality of the paths that connect the nodes can be used to solve the problem then displaying and distinguishing the plurality of the paths that connect the nodes that can be used to solve the problem; and solving the problem by the computer to determine a value for the at least one unknown variable based on the user input and the first concept map of the displayed concepts and the first path.