How Data-Driven Decision-Making Helps Drive School Improvement

Deborah Dowling is the Executive Director for the California Association of Independent Schools (CAIS) and a keynote speaker at the ERB Connections Western Regional Conference in Pasadena, California.

The reason strong schools find it useful to collect data is to help them make important decisions.

Sometimes, standardized assessments, dashboards, multi-year databases, and other sources of numerical information about a school can be seen through the enthusiastic lens of: “Look at all these facts! How wonderful to know so much!” In other cases, that same information can be viewed more negatively—as meaningless figures that pile up without purpose. Both perceptions miss the role of a data set as a decision-making tool, in a process that starts with well-framed, action-oriented questions.

As a school administrator, it’s your job to make decisions. Do our programs, curriculum, or pedagogy need to change? If so, how? Who will be affected? Now that we have made a change, did it have the result we wanted? What requires our attention next?

Data sets help us answer those questions in ways that drive action:

  • If the data show X, then we should do A.
  • If the data show Y, then we should do B.

I challenge you to take a moment to make a note:

  • What decisions do assessment data help you and your school to make?
  • What decisions would you like assessment data to help you and your school to make?
  • Why do those decisions matter?

That last challenge—why do those decisions matter?—may be the most difficult of the three. The answer may tie back to the school’s mission, its policies on admission and inclusion, or the students’ needs as they prepare for the next stage of their lives. Those factors all give ERB and other data sources purpose and meaning.

Data and Accreditation: Building a Culture of Continuous Improvement

Meaningful, purposeful, data-driven decision-making in education is at the core of what my colleagues and I do at CAIS: we accredit schools. 

Your school is almost certainly accredited, either by CAIS or a similar organization. The accreditor is typically a national or state organization that periodically visits the school, checks that baseline standards are met, and guides the school to improve. When the time comes for your school to update its accreditation status, your expertise with regard to student assessment data will be a vital asset.

During the “self-study” stage of accreditation, schools use data to show thoughtful, evidence-based analysis of the strengths and weaknesses of their programs, and they point to the ways data have helped them answer questions, make decisions, drive change, and evaluate success. 

A culture of inquiry and growth should flow into the classrooms from the broader community of faculty, staff, and administration, who are inspired to reflect deeply on what is working at the school, figure out where there is room for improvement, engage in carefully planned action, and then evaluate the effects of change.

By engaging everyone in the school actively in the process of reflection, self-evaluation, and improvement, accreditation can help the whole community model the same growth mindset and openness to learning that helps our students succeed.


“A culture of inquiry and growth should flow into the classrooms from the broader community of faculty, staff, and administration.”

Deborah Dowling, Executive Director, California Association of Independent Schools


Using Data for Evidence-Based Decision-Making

All areas of school improvement work best when they are based on strong evidence. At CAIS, our accrediting teams look for schools that collect data in multiple forms from multiple sources, to drive their thinking, test their hypotheses, and evaluate outcomes. If your school uses assessment tools (such as those offered by ERB), then it is already in a good position: your school systematically collects detailed data about its students’ skill development and growth in academics, well-being, and social and emotional learning.

Let’s take a look at some typical questions from an accreditation self-study process.  These questions are taken directly from CAIS’ self-study manual for member schools’ accreditation.

  • Describe and evaluate the rationale, process, and outcomes of the school’s most recent significant curricular changes.
  • Give an example of how the school disaggregates data to explore potential differences in student learning that may connect with race, ethnicity, gender, socio-economic status, ability, or other socially significant factors.
  • How does the school assess students’ social emotional learning?

Without the systemic collection of data, these can be very difficult questions to answer. With standardized assessments, however, schools can show accreditors the care with which they support students’ needs. Here is an example of an excellent self-study response:


“To measure the success of the new 8th grade writing program, we looked at the increase in students’ writing test scores from 7th grade to 9th grade. We compared the increase for students who took the new program with the increases we saw for the three years before we introduced the program. We also used feedback from the middle school English teachers about factors such as student motivation.”


Of course, assessment data are only one piece of evidence. Maybe the ninth-grade writing assessment scores improved because the school changed its admission criteria, because class sizes changed, because the test was taken later in the year, or because the testing site was moved. Perhaps it was the Hawthorne effect: students did better because any new writing program comes with increased attention to skill development, regardless of how good the program is. 

Regardless, it is essential to back up the conclusions suggested by standardized assessments with other evidence, such as teacher insights from their daily interactions in the classroom.

Using Assessment Data to Support Your School’s Accreditation

The best data sets for supporting school improvement are able to show long-term, year-to-year comparisons. That is why, regardless of how many years there are until your school’s next accreditation visit, now is always a good time to set up routines of data collection and analysis.

Specific questions and decisions will come and go: did this program make a difference to students’ skills? Should we continue with that intervention to help a particular group? The long-term data that will provide answers to those questions will depend upon consistency: clearly defined groups (grade-level cohorts, demographic subgroups) taking normed, standardized assessments routinely, year upon year, in clearly defined skill sets (writing, math, and so on).

When it comes time for your next self-study, what data analysis routines will you have put in place to help your school demonstrate excellent, evidence-based decision-making?


Deborah Dowling dove deeper into data-driven decision making in education as a keynote speaker at our ERB Connections Western Regional Conference, where she spoke about how educators can use data to drive meaningful action. This event was part of ERB’s new conference series with events also in Houston, Atlanta, and Philadelphia, open to both ERB member and non-member schools.

About the Author

As Executive Director of the California Association of Independent Schools, Dr. Deborah Dowling oversees the accreditation of independent schools in California, and provides professional development opportunities for the heads and trustees of member schools. Previously, Deborah held the roles of Assistant Head at Chadwick School, Upper School Director at Bridges Academy, and Director of Studies at Harvard-Westlake School. Originally from Melbourne, Australia, Deborah holds a bachelor’s degree in physics and a doctorate in the history and philosophy of science. She has taught a variety of subjects from kindergarten through undergraduate. Deborah lives in Los Angeles with her husband, Andrew, and two large dogs, Buffy and Willow.

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