In most states across the country, public K-12 enrollment is declining. This is a decade-long, national trend that accelerated with the onset of the COVID-19 pandemic and is projected to continue. Although enrollment decline varies substantially among and within states, many states have put temporary or permanent policies in place to address the budgetary implications of enrollment decline. In cases where a school system is growing rapidly, state governments can also allocate additional funding to districts to account for expansion. Different policy choices for states to respond to enrollment change come with trade-offs: The costs of additional support for some districts means that relatively less state aid can be put toward other educational priorities. This reports discusses the following questions: (1) How do states count students for school finance purposes?; (2) How do states approach funding for districts experiencing enrollment decline?; (3) How do states approach funding for districts experiencing enrollment growth?; and (4) How should states weigh trade-offs?