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April 4, 2011

Student Achievement in the Cobb County School District – Is the Balanced Calendar Working?


I’ve previously published research regarding the Cobb County School Board’s decision to revert to the “traditional” calendar.  Much to the dismay of the board members, many of the parents have not let this unpopular change go away.

In a very rare move, the Cobb school board was called to testify in front of a grand jury to discuss the recent calendar decision and the board’s overall decision-making process.  The outcome/recommendation from the grand jury will likely not be known until early-May.

The remainder of this blog post contains excerpts from research conducted by a friend and fellow Cobb County parent with respect to academic gains achieved to-date under the “balanced” calendar.  View the research in its entirety here or see the bottom of this post.

In November of 2009, the CCSD approved a balanced calendar for a three-year period to begin in 2010-2011. The district committed to monitor the impact of the balanced calendar on key operational areas including student achievement.

On February 17, 2011, the Board of Education overturned this decision before the first year under the balanced calendar had even been completed, approving “traditional” calendars for the following two school years. Although this reversal was shocking, even more stunning was the fact that the board overturned its 2009 decision without honoring the commitment made to the district when the balanced calendar plan was established.

Because the 2010-2011 school year has not yet been completed, a full assessment of student achievement under the balanced calendar is not possible. However, the three assessments completed to date – The Iowa Tests of Basic Skills (ITBS), The Georgia High School Writing Test (GHSWT), and the End-of-Course Test (EOCT) – can provide some insight into the impact of the balanced calendar on student achievement.

The Iowa Tests of Basic Skills (ITBS)

Students are assessed in the fall on the Iowa Tests of Basic Skills (ITBS). This is a norm-referenced assessment that measures student achievement in comparison to other students nationwide. Students in grades 3, 5, and 7 are tested in Reading, Mathematics, Language Arts, Science, Social Studies and Sources of Information.  Results include:

  1. ITBS Grade Equivalency (GE) scores for Cobb’s third, fifth, and seventh graders had all been declining in recent years. However, for the first time since 2007, ITBS GE scores in Cobb County increased in 2010
  2. In 2010, GE scores for third graders increased to 3.59, an increase of 3.5% in just one year
  3. GE scores for fifth graders increased 1.8% in 2010 to 6.05
  4. GE scores for Cobb’s seventh graders increased slightly by 0.6% to reach 8.05 in 2010
  5. Percentile rankings for all three grade levels increased by 1.5% in 2010

The Georgia High School Writing Test (GHSWT)

High school students are assessed on the Georgia High School Graduation Tests (GHSGT) and the Georgia High School Writing Test (GHSWT). Most students take the GHSWT during the fall of their junior year and are required to pass the test to earn a regular education diploma.  Results include:

  1. GHSWT results improved by 3.3% in 2008 with 95% of the students passing the assessment
  2. Results declined slightly in 2009, falling to 94%
  3. Results have increased dramatically in 2010 with a 4.3% increase to an all-time high of 98%

End-of-Course Test (EOCT)

All students take the End-of-Course Test (EOCT) after completing various courses in four different categories: English and Language Arts (ELA), Math, Science, and Social Studies. Results of the EOCT are used for diagnostic, remedial and accountability purposes to gauge the quality of education in the state and also count as part of the student's final grade in the course.  Results include:

  1. Results in ELA and Social Studies have maintained a slight but steady increase through the 2010-2011 school year
  2. Results in Science showed a slight decrease in 2010-2011, returning to their 2008 level of 71%
  3. After a 23% decline in 2008-2009, results in Math dramatically improved by 26% in 2009-2010. They continued to improve by another 11% to 75% in 2010-2011, reaching a level not obtained since 2006-2007


Quantifiable year-to-date student achievement in the Cobb County School District during the first year of the Balanced Calendar can be summarized as follows:

  • ITBS Grade Equivalency scores and national percentile rankings had all been declining in recent years but increased in 2010-2011 for the first time since 2007
  • GHSWT passing rates had improved in 2008-2009 and declined in 2009-2010, but then they increased dramatically in 2010-2011 to an all-time high
  • In 2010-2011, EOCT passing rates declined slightly in science, continued a steady increase in ELA and social studies, and continued to increase significantly in math

Of course, the results of only three assessments cannot definitively establish the impact of the balanced calendar on student achievement. Ten total assessments are published each year in the CCSD, and full evaluations of all ten at the end of the 2010-2011 and 2011-2012 school years would have provided the most reliable gauge of the balanced calendar’s impact.

However, these are the only assessments that have been completed to date, and one thing can be said for certain. The balanced calendar has not had an adverse affect on student achievement in the Cobb County School District to date in 2010-2011. In fact, all indications so far suggest that the balanced calendar has had a positive impact on student achievement and is promoting improved results.


  1. So if the Cobb County School Board is acting in the best interest of the children in the schools why have they decided to revert to a calendar that was in place when performance scores were lower?

  2. Precisely the point. They're clearly NOT acting in the best interest of the children, but in their own.

    It's funny how survey results are deemed as bogus when they aren't the results they want. However, it's used to justify other decisions.

    Politics at its worst!

  3. I agree. In a year that has seen some of the ugliest politics on the national scene, this is truly politics at its worst. The people who are elected to the school board have one function - to make responsible decisions that are clearly in the best interest of the students in this district. In discharging their duties, four of the board members have also disregarded the fact that student and teacher absenteeism have declined. This contributes a great deal to both improved student performance and decreases CCSD expenditures in the area of substitute teachers. Certainly a grand jury investigation is called for because as evidence mounts that this "balanced" calendar is a positive for the district, clearly something more than campaign promises are afoot.

  4. The CCSB appeared before a grand jury on Apr 1, with the report back expected in early May.