Spotlight on Enrollment

With the 13-14 school year over, school districts nationwide have begun preparations for 2014-15.  One of their highest priorities is to ensure a teacher in every classroom.  Seems basic, right?  Yet one might be amazed at the number of schools who don’t have enough teachers, or who have teachers in the wrong place, when schools open in September.  

One of the biggest challenges is intra-district population shifts.  If the families of  twenty children move from Neighborhood A to Neighborhood B over the summer, the school that serves Neighborhood A needs to find seats in classrooms for those 20 children.  However, too many school districts do not factor summer population movement into their plans and assign all their teachers to start the new school year at the same school where they ended the last one.  As a result, the teacher that Neighborhood A’s school needs might be waiting across town in Neighborhood B with an empty classroom.

A technique called cohort survival analysis (CSA) can improve school districts' ability to predict how many kids each school will have.  CSA uses previous enrollment patterns at each school to predict the enrollment for the coming school year.  

In the example below, School A had 37 second graders in 2011-12 and 39 third graders in 2012-13.  In CSA terms, School A kept 37 children and added 2 more.  School A had 41 2nd graders in 2012-13 and 37 3rd graders in 2013-14, so CSA considers the school failed to retain 5 students in the move from second to third grade.

First, CSA calculates the average rate at which schools enroll students as a function of the size of a school’s population one grade below in the previous year.  For School A, the survival rate for 2012-13 third graders equals

12-13 Third Graders               =          39        =          105.4 percent
11-12 Second Graders                       37

Likewise, the survival rate for 2013-14 equals

13-14 Third Graders               =          37        =          90.2 percent
12-13 Second Graders                       41
 

To project the enrollment of 2014-15 third graders, we average the previous two years’ survival rates and apply the product to 2013-14 2nd graders.  This process shows that School A had a 97.8 percent survival ratio for third grade over a two-year period.  

(12-13 Survival Rate)+(13-14 Survival Rate) =          105.4+90.2      =          97.8 percent
                                      2                                                                  2

Then we multiply the number of 2013-14 second graders (32) by the two-year survival rate for third grade, which equals 31.2.  Most districts rounded all projections up, so the final projection is that School A will have 32 third graders in 2014-15.

14-15 Third Graders =          13-14 Second Graders*.978   =          32*.978           =          ~32

Using CSA, AEM can generate projections for both the total number of students in each school in your district and the size of the populations of English language learners, special education students, and any other subgroup for which your district has data.  AEM will work with your district personnel to understand the ways in which we should incorporate things like new housing starts into the final projections.  We can also use established techniques to extend your projections even further into the future, so that you can predict how many students your district will have  five or more years down the line.

Whatever your needs, AEM will employ the best techniques  to ensure you have the most accurate enrollment information for the coming school years.  For more information, please contact us.

Elizabeth Sobka