Data, data everywhere but not a drop to drink.

That's what many principals have concluded after gaining access to more data about teachers' past performance without understanding how to make the most of it during hiring. A recently published study by Marisa Cannata (Vanderbilt University) and her colleagues at the University of Michigan and North Carolina State University examines this challenge and identifies big and small steps district central offices can take to remedy the problem. Namely, the study highlights the need for districts to communicate about data availability and help principals use data to complement their professional judgment.

The researchers surveyed nearly 800 principals in multiple districts and followed up with a selection of interviews. Many principals are proactive in their approach to gathering relevant data (for example, they may ask applicants to bring previous teacher evaluations with them) and systematic in their approach to assessing a teacher's fit within their school. One principal describes a clever way to use his district's evaluation rubric for demonstration lessons:

….then we debrief about [the demonstration lesson] and even if [it has gone] well, it could still kind of lead to non-hire depending on how the debrief goes. We like to test that too, to see, "Okay, I've got to give them some feedback that's not all positive, and see how they can handle it." […] I'm not trying to be too critical, but if they're very combative right then and there, I go, "okay, maybe this isn't a good fit because we're going to be doing a lot of this throughout the course of the school year."

Other principals may not be as willing to go the extra mile to collect relevant data. In one district, a principal explained that while she didn't automatically have access to all the data she would like, reaching out to the district office to get that information was quick and easy. A fellow principal in the same district couldn't say the same—

It's not like I have a magic number I can call and go, "hey, can you get me…"
No, that's not how it works, and I wish it did.

Districts still have work to do to get principals on the same page about data quality and limitations, particularly when it comes to value-added data. As one VAM-skeptical principal explains:

I rarely use the [value-added] data in hiring just because I think that there's so many factors involved in [it] that it's hard to just look at that individually without knowing a person and watching them teach.

If this study makes one thing clear, it's that the distance between data collection and data use is long; bridging that gap will require comprehensive support and ongoing input from building leaders.