Will increasing Kentucky’s minimum high school dropout age to 18 improve high school graduation rates?

It’s a question everyone is asking, including state legislators. Tomorrow, the House Education Committee is scheduled to hear a bill that will raise our dropout age to 18.

To be very clear on this, if it works, that will be great.

But, it will be expensive to house these students in our school system until Age 18. Many leave at Age 16 and 17 today.

Also, forcing these kids to remain in school has the potential to create some highly alienated students on our high school campuses. That alienation could manifest itself in ways that could disrupt learning for serious students and could create potential for serious security problems.

Finally, I asked a question of several groups that have looked at this issue. It turns out the research is rather thin to support moving to Age 18 for dropping out.

When Massachusetts looked at similar legislation in 2009, the Rennie Center published a study titled, “Raise the Age, Lower the Dropout Rate?”

This 18-page report does a very nice job of outlining the pros and cons along with a survey of the available research. The Rennie Center says:

“Our review of research revealed little evidence to support the idea that raising the compulsory age to 18 decreases dropout rates and increases graduation rates.”

Later, the report says:

“We urge policymakers to first consider other policies to address the Commonwealth’s dropout crisis.”

One research example cited in the Rennie report compares the year states moved to Age 18 dropout minimums and the states’ performance with the Averaged Freshman Graduation Rate statistic that is now reported by the National Center for Education Statistics. The data only ran to the 2004-05 school year, so I took a look at the now available AFGR data to 2007.

This graph shows which Age 18 dropout states showed a positive or negative trend in their graduation rates between 2001 and 2007 (click on it to enlarge).


As you can see, the trends are about evenly divided. Eight states that had enacted an Age 18 minimum dropout age by 2001 improved their graduation rates between 2001 and 2007. In fact, three of those states, Ohio, Oklahoma and Kansas, had improvements that were scarcely more (only a few hundredths of a point) than the national average improvement.

Seven jurisdictions actually saw a decline in their graduation rates while the rest of the nation was posting improvement (*Note: Nebraska changed to Age 18 in 2004, but had four years of data to determine a useful trend line and therefore is also included).

Overall, only five of the 15 states in the graph – Hawaii, Wisconsin, Oregon, Washington and Connecticut – had graduation rate improvements notably above the overall national average improvement from 2001 to 2007.

This graph and the more extensive comments in the Rennie Center study indicate that simply raising the dropout age to 18 isn’t a sure cure for low high school graduation rates.



Technical Information

Averaged Freshman Graduation Rates (AFGR) for each state were obtained from several years of the Digest of Education Statistics and other documents from the National Center for Education Statistics (NCES). The AFGR was extensively researched by the NCES in the early part of the decade and the findings were made available in a two-volume report, “User’s Guide to Computing High School Graduation Rates,” in 2006. Per NCES, the AFGR represents the best comparison data currently available on high school graduation rates for the 50 states.

I picked 2001 as the starting year for my analysis because the US average AFGR was in decline until the turn of the century and then began to increase again through 2007. Thus, any state with a small increase or even worse, a decline, in its graduation rate would be performing below the national norm.

Most of the information concerning the first year the Age 18 minimum was adopted in each state was obtained from an e-mail from the Education Commission of the States – My thanks to Jennifer Dounay Zinth of the ECS for compiling that information. I also relied on information in the Rennie Center report and in a 2008 Scripps Howard news release for a few states where ECS was unable to locate data.

I did not examine states that had only two or one year of experience with the Age 18 minimum as of 2007, as these states offered insufficient data.

Once those states with at least four years of Age 18 graduation rate data were determined, I ran a regression analysis to determine the slope of the best fit line for the data points for each state. Those slopes are shown in the graph.