Households in urban ecosystems contribute substantially to biogeochemical cycling, but what influences particular household choices and can this understanding improve attempts at pollution management? We developed a mathematical computer model (Household Flux Calculator, HFC) that calculates the fluxes of elemental carbon (C), nitrogen (N), and phosphorus (P) for individual households based on a variety of household behaviors and decisions, such as energy use, transportation, diet, and lawn management practices. Preliminary results imply that human choices made within households can have a major influence on fluxes of C, N, and P. The HFC model was used to analyze behaviors and associated C/N/P collected from household interviews in a pilot study in Falcon Heights, Minnesota, an upper-middle class first-ring suburb of the Twin Cities. We analyzed specific behaviors and respondent qualitative explanations for why they made particular choices. Using the Theory of Planned Behavior provided insights into critical measures that could influence the key decisions - knowledge, attitudes, norms, and perceived control. We discuss challenges for measurement and causal arguments in complex household decision making, with attention to spatial and time scales. Understanding what influences household choices could assist in designing policy to influence behaviors in pollution management.