Many school nurses experienced increased work burden and stress during the COVID-19 pandemic. This analysis examined data from a Centers for Disease Control and Prevention cross-sectional, nationwide survey of school nurses in March 2022 to examine associations between school nurses' ability to conduct their core responsibilities and selected nurse and school factors among school nurses during the 2021-2022 school year and COVID-19 pandemic. Perceived adequate staffing and financial compensation reduced the odds of reported difficulties across all core school nursing tasks. Nurses without a registered nurse license and with higher caseloads were more likely to report difficulty in implementing specific tasks. The impact of these factors varied, with inadequate financial compensation having the largest association with school nurses' difficulty implementing all the core responsibilities. The study results improve our understanding of school nurses' challenges in implementing core school nursing responsibilities during the COVID-19 pandemic in the 2021-2022 school year.