This project will utilize the two 26 m radio telescopes at the Pisgah Astronomical Research Institute to revitalize the field of long-term monitoring of flux variability in cm-wavelength radio sources. The results will determine or constrain intrinsic characteristics of potential variable sources such as active galactic nuclei, and can help characterize the ionized interstellar medium in our own galaxy which imparts scintillation and, on rare occasions, extreme lensing effects that impact the flux of background radio sources. The Pisgah facility has an established record of involving undergraduates in its research programs, including those from historically non-research-oriented institutions in North Carolina and South Carolina.