We study the progressivity of state funding of school districts under Tennessee's weighted student funding formula. We propose a simple definition of progressivity based on the difference in exposure to district per-pupil funding between poor and non-poor students. The realized progressivity of district funding in Tennessee is much smaller--only about 17 percent as large--as the formula weights imply directly. The attenuation is driven by the mixing of poor and non-poor students within districts. We further show the components of the Tennessee formula not explicitly tied to student poverty are only modestly progressive. Notably, special education funding is essentially progressivity-neutral for poor students. If we adjust the formula so all factors except individual student poverty receive zero weight and distribute the excess to poor students, we can increase the progressivity of district funding by 124 percent. We interpret this as the opportunity cost of the non-poverty-based funding components, measured in terms of progressivity.