Background: School nurses play a vital role in ensuring the health and well-being of their students, but little is known about menstrual products and resources available in schools. This study assessed period product resources and needs in Missouri schools from the perspective of school nurses and analyzed differences by district enrollment characteristics. Methods: An electronic survey was emailed to public, charter, private, and parochial school nurses in Missouri who served fourth grade or older. From January through March 2022, 976 self-administered surveys were completed (40% response rate). Logistic regressions examined the associations between student needs and district characteristics. Results: Among the sample, 70.7% knew students who could not afford period products, and 68.0% knew students who had missed school because of their period. When controlling for district size, race/ethnicity, and urban/rural classification, as the percentage free- or reduced-lunch (FRL) eligibility increases in a school, awareness of students struggling to afford products increases (AOR = 1.008, 95% confidence interval 1.000, 1.015). Implications for School Health Policy, Practice, and Equity: School nurses need the resources and educational materials to support students to help reduce menstruation-related absences. Conclusions: Issues of period poverty cut across districts of differing enrollment characteristics, yet FRL percentage is an important predictor.