The NOvA experiment is an off-axis long-baseline neutrino oscillation experiment using the NuMI beam originating at Fermilab. To attain its physics goals---which include addressing prominent open questions in neutrino mixing including CP violation and the neutrino mass hierarchy---the experiment requires a robust model for neutrino interactions in the detectors and a firm grasp of any associated uncertainties. In this talk I will discuss how NOvA is progressing towards that goal despite the challenges associated with modeling few-GeV neutrino scattering in the complex nuclear environment of hydrocarbon. In addition to surveying the foundations of the physics in the GENIE generator that we use as our base model, I will explore the modifications we make to it based on evidence from other experiments as well as that from our own near detector. I will conclude with some thoughts about future insights we hope to gain about cross section models using NOvA's vast dataset.