Resources and Tools

By Kristen E. Humphrey, MLA, Local Assistance and Training Planner and
Alfred Sundara, AICP, Manager, Projections and State Data Center

Each year as part of The Maryland Department of Planning’s statutory mandate to support Maryland’s public school systems, the Maryland State Data Center prepares public school student enrollment projections that look ten years into the future for the state’s more than 1,400 K-12 public schools. These projections are shared with the state’s twenty-four Local Education Agencies (LEAs) which represent Maryland’s counties and Baltimore City.

In turn, the LEAs share their own enrollment predictions, and then the two sets of data are compared. To finalize the numbers, the State Data Center and the LEAs’ projections must be within 5 percent of each other (i.e., a 5 percent tolerance). If an LEA’s projections are not within 5 percent of the State’s, the LEA and Planning review their data together to determine the reason for the discrepancy and arrive at a resolution.

This involves reviewing methodologies of both the State Data Center and the LEA and understanding the assumptions for the projections and adjusting them based on feedback from both the parties. While preparing projections is statutorily required, the exact methodology is not. This is because there is more than one way to arrive at an answer, neither of which are wrong…just different. 

Additionally, the LEAs may have specific information regarding residential building permits in their county that Planning would not have. For example, an LEA may be aware of an upcoming large construction project, such as a new housing development or large apartment building, that is likely to impact a particular school or “school cluster;” like a local high school and its middle and elementary feeder schools. Such a project would impact the cluster by increasing enrollments by the number of school-aged children anticipated to live in that development or building.

Why Are School Enrollment Projections Important?

Schools have come a long way from when we were children, and it is no secret that building a school is a very expensive undertaking and takes a long time to plan, finance, and build. Elementary schools can cost in excess of $40-50 million, middle schools $70-80 million, and high schools are often upwards of $100 million to construct. Planning, design, and construction can take a number of years with costs increasing annually. Thus, having some idea of whether a county’s K-12 student population is on the rise or decline, not to mention what is happening in various age groups, can help LEAs determine whether new schools, additions, or even school closures may be on the horizon. Planning’s projected numbers for the 2019 school year were spot on at 99.4 percent of the actual number, only off by 0.6 percent!Many factors come into play. How many children are born each year, and of those, how many will by age five enroll in public kindergartens, or perhaps move into or out of the area? How many will attend local public schools vs. private schools or be home-schooled? The projected answers to these questions are essential data. Additionally, projections need to distinguish between temporary fluctuations in populations, or “population bubbles”, as opposed to long-term trends.

Finally, future enrollment projections will need to predict even more specific demographic trends. For example, the number of students who may need English as a second language (ESOL) or those who may need other types of specialized instruction affecting classroom size and other facility needs. Not surprisingly, the calculations involved in accurate projections become very complex, very quickly. So how are these calculations made?

Planning has honed its technique for accurate enrollment projections based on a grade succession ratio methodology using a combination of demographic data from the U.S. Census from 1990-2010 and the 2009-2011 American community Survey (ACS). This underscores the tremendous importance of accurate U.S. Census reporting as the relationship between this data and the resources available for state and local funding of school construction projects is inextricably linked. This is, by the way, another area in which Planning plays an important leadership role (See January 30, 2020 and May 29, 2019 Planning Practice Monthly articles regarding Census 2020 to learn more about our efforts.) For continuous updates regarding the 2020 U.S. Census, taking place now, visit the Maryland Census 2020 website and sign up to receive our Census-dedicated newsletter.

Planning will explore the grade succession ratio methodology in more depth in an upcoming edition of Planning Practice Monthly, when we will also publish this year’s Maryland Public School Enrollment Projections. Until then, please refer to Planning’s webpage dedicated to 2018 historical and 2019-2028 enrollment projections or contact Alfred Sundara, Manager of Planning’s Projections and State Data Center at 410-767-4002 or alfred.sundara@maryland.gov.