This was written by Úrsula Casanova, asssociate professor emerita at Arizona State University.

By Ursula Casanova

School administrators across the country have been expressing their concern over the federal government’s changes in reporting graduation rates. Starting with the 2010-2011 school year, all high schools have been required to provide data based on the four-year “cohort” rate. In some states this method has already resulted in graduation rates as much as 20% below those formerly reported.

That should not surprise those who availed themselves of the summary data on schools available on the web from government sources. The data for each public school includes a breakdown of the number of students at each grade level for a given year. Thus you can see the difference between the number of students who entered the school as freshmen, and the number of seniors who were there to graduate four years later.

While a school may proudly claim that they graduated all their seniors, a more intensive examination of that school’s summary data may show that between 2006 and 2010, that school’s student population had dropped dramatically.

The Basis (Charter) school in Scottsdale, Arizona, is a good example. Basis Scottsdale was named the top high school in Arizona based on its score on Arizona’s AIMS test, the test used to comply with the No Child Left Behind law. As is true of most charter schools, Basis Scottsdale was able to select the grades they wanted to offer and chose to instruct in grades 5 – 1 2.

The National Center for Education Statistics tells us how many students were enrolled at each of those grades during the 2009-10 school year. Beginning with the 5th grade we find enrollments of 152, 138, 110, and 94. By the ninth grade (freshman year of high school,) the number of enrolled students had decreased to 42, then to 30, 23, and, finally, as graduating seniors, there were 8 students remaining! Thus, while they graduated all their seniors, those students were less than 20% of the current freshman class (and only 5% of the current fifth grade enrollement). We have no data to inform us about the number of students in the fifth grade or ninth grade in this school when the graduating class of 2010 was in those grades. But the small size of the graduating class suggests it is only a fraction of the students who once attended Basis with the surviving seniors.

We also do not know the characteristics of those who dropped out along the way in comparison with those who stayed in this school, but dropouts are not random. They have certain characteristics: They may be harder to teach because they have special educational needs or they are language minority children, or children who do not meet the behavioral standards of the school. Clearly, such non-random dropouts ensure a more selective student body.

This pattern is repeated across many schools. For example, the second highest scorer on the AIMS (Arizona’s Instrument to Measure Standard) test: BASIS, Tucson, also offers grades 5 – 12. The decline is slightly less steep for the “second best high school in Arizona.” They started out with 127 students in the fifth grade, had 129 in 6th, and 130 in 7th, then the numbers began to decline rapidly: 100 in eighth grade, and 69 in 9th, the freshman year for high school. But those numbers went down further, to 45 in 10th grade, 27 in 11th, and at the end, they had only 24 seniors left for graduation. The graduating class was only 35th % of the current ninth grade cohort, and they were less than 20% of the current fifth grade cohort. This kind of enrollment drop across grades is repeated across many different schools, not only in Arizona, but across the country.

Take, for example, Newsweek’s 2011 selection of the 500 BEST High Schools in the USA, based on strict, recently modified, criteria with six components and values: Graduation rate (25%), college matriculation rate (25%), and Advanced Placement (AP) tests taken per graduate (25%) are the three most important factors. But they also used the average SAT/ACT scores (10%), average AP/IB scores {International Baccalaureate)(10%), and AP courses offered per graduate (5%).

The School of Science and Engineering, a selective magnet school in Dallas, was at the top of the list for 2011. It graduated 87 students, only 67% of the original numbers for the (9th grade) cohort.

The High School for the Talented and Gifted, also a selective magnet school in Dallas, came in third in the Newsweek list. Their 229 students are distributed unevenly across the four grades. Sixty-eight students are reported for the ninth grade, 56 in the sophomore class, a slight rise to 60 in the junior year and then a drop to 45 in the senior year. Thus, once again, it appears that at this small, selective school, only about 60% of the numbers of entering students make up the graduating class four years later.

This pattern of decrease in enrollment over the years is repeated across many of the nations’ “best” high schools. The purpose of this discussion is not to argue that the selected schools are bad schools but rather to bring up another important factor when we engage in rating our nations’ schools.

I began this discussion with the Department of Education’s announcement about a change in the reporting of high school completion. My endorsement of this change is based on my own research on school dropouts, a topic the nation now takes very seriously. But we need to pay attention, as well, to those schools, especially large ones, that maintain their population through the four years of high school.

San Luis High School in San Luis, Arizona, is one of these. This public high school serves over 2,500 students, almost 100% of whom are Hispanic, and appears to graduate 91% of its students (657 freshmen to 597 seniors). They also do this with a teacher pupil ratio that is almost double the U.S. average, as well as with Arizona’s per pupil school funding, which is among the lowest in the nation. How does San Luis manage to do so well against such great odds? Why is it not on someone’s list of great American high schools?

On the other hand, why aren’t the raters of schools questioning the big drop in school enrollment across years in selective schools or in charters? How do the numbers in these schools compare to those of ordinary public schools? Where do the missing students go? I am happy to see that Newsweek has made changes in order to do better at selecting the best, but they seem to be ignoring the fact that there may be many ways to be “best.” Although the criteria selected may be appropriate to find out how well a high school prepares students for college, it doesn’t tell us what happened to those who never made it to their senior year.

If some kind of manipulation is occurring in charters and in selective schools, as seems possible given documentation of big enrollment drops across grade levels, and then heavy weights in the school rankings are given to the graduation rate, the college matriculation rate, the AP tests taken per graduate, and to scores on other tests, then the schools may be inappropriately rewarded with a higher rank for engaging in skimming and creaming their students.

The federal government’s mandate for better information about all of our nation’s schools now requires the inclusion of the cohort size in relation to their senior class. It is a step in the right direction. I hope Newsweek and all the other people and organizations that rank schools in years to come will include the new cohort rate data in their analyses.


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