Among the many factors that impact student performance in traditional K-12 settings, parent involvement (PI) is consistently identified as critical for student success. However, less is known about parent involvement for full-time virtual schools, where most learning takes place asynchronously in a Learning Management System (LMS). The present study attempts to close this gap by using data from three virtual schools' LMS to measure the impact of parent involvement on mathematics achievement, across grade bands where PI is known to vary. After controlling for factors known to impact education outcomes, parental involvement - as measured by LMS logins - had a small, but positive, impact on student performance in mathematics across elementary, middle, and high school. These results, coupled with the elevated role of the parent, suggest that parental involvement is just as critical, if not more so, in virtual schools as in traditional settings.