Guest post from Amy Baeder, who is a teacher educator and doctoral candidate at the University of Washington

After giving birth to my daughter, who is now 6 months old, I decided that it was time to start working on shedding my remaining 10 pregnancy pounds. My first step? Start keeping track of the calories I take in using a smart phone application. After laboriously logging each and every morsel and drop that entered my mouth, I had a day's worth of data. I couldn't help but think about all the data we collect as educators and how that data links (or, more often than not, doesn't link) to our teaching performance. Why do we collect data? What impact does collecting data have on the data itself? How often do we collect data without making any changes? The parallels between collecting data with the ultimate outcome of student learning and collecting data with the outcome of weight loss are worth thinking about as we go about our daily work as educators, especially considering the current moves of many districts to student outcomes-based evaluations.

Day 1 of logging my calories was miserable. I realized how much I was relying on quick, fat-laden, carbohydrate-rich and nutrient poor foods to sustain me as I juggled my wiggly daughter in one arm and a container of leftover macaroni and cheese in the other, attempting to shove it in the microwave and then into my mouth. But, I recorded my intake, watched the calories rack up, and looked at the results at the end of the day. I didn't change the way I behaved due to a lack of energy and healthful foods, but I was aware of my nutritional transgressions.

I immediately recalled my years as a teacher, before maternity leave, and especially my first years of learning about formative assessment. Did I have data? Yes, indeed! I assessed my students through warm-ups, written formative assessments, discussions, pretests, and summative exams. I knew a quite a bit about what my students knew, but, like my cabinets lacking wholesome food, my knowledge about what to do with all of this data was lacking. How do I attend to what students need? What are my next instructional moves? How do I use this information in useful ways that lead to positive outcomes for student learning? More teachers will be thinking about these questions more urgently in light of recent shifts in how they will be evaluated, but because these are not easy questions to answer, some teachers choose to continue to endlessly collect data.

Day 2 of logging my calories led to a second realization—the very act of logging my calories made me reconsider, to a degree, what I chose to eat and thus record. This type of attention to our actions when being recorded or observed happens in classrooms every time an administrator does a walkthrough, every time a classroom is videotaped, or whenever we, as educators, make our practice public. If we know we are being watched, we may change our actions slightly, but the change is usually surface-level unless we go about changing with a well-developed plan in mind. For instance, early in my teaching career, if I knew an administrator was coming to observe my lesson, I would be sure to have the kids "do something hands-on" for the period. Was I was certain to build in sense-making for that activity, scaffolds for building academic language, or modifications for students with special needs? It wasn't likely, because I didn't yet have the tools for doing this. As districts implement new ways of evaluating teachers, it will be their responsibility to provide teachers with high-quality professional development that provides teachers with the strategies they need to move past superficial changes in their teaching.

Day 3 of keeping track of my calories resulted in different outcomes, but this was no accident. Unlike days 1 and 2, I had healthy snack and meal options in stock, a plan for what I was going to eat, as well as an exercise time allotted. I had to put forth time and energy before the day began, but it paid off. My calorie intake was less than my calorie output for Day 3. I had moved from passive data collection to intentional data influencing, and the same can be said for certain classrooms, districts, and schools. Like Day 3 of "Operation: Lose Baby Weight," my teaching career had a similar pivotal moment that occurred about 4 years ago when I learned that data collection alone is not enough.

I had been religiously giving students formative assessments and was continually disappointed by the results. I was teaching—why weren't kids getting it? Perhaps it was because I was teaching the same way I would have if I hadn't given them the pre-assessments. I had file folders full of formative assessments—lots of data—but I didn't know what to do with it. I had empty cupboards and no plan, in other words. What changed my thinking was a workshop organized by the science coaches in our district featuring a guest speaker on diagnostic teaching.

Although the speaker's name escapes me, the message he shared did not. I learned how to connect formative assessments to learning experiences that students need. He gave us a one-pager with a variety of learning experiences that might connect with various "holes" in students' thinking. He had us sort through our formative assessments, discover where the gaps in student thinking were, and design a differentiated lesson to meet those needs. Did students misunderstand the role of light in photosynthesis? Perhaps they need a lab designed to meet this need. Are there three different subgroups with varying misconceptions about digestion? Perhaps a jigsaw reading activity will assist students in shaping their thinking. This realization of teaching to the needs of my students should not have been so revolutionary at that point in my teaching career, but nevertheless, I was grateful for it. I was making the data work for me and for my students, and I had a plan.

So is my teaching perfect? No, and neither is my diet, but I can safely say I am no longer collecting data for no reason. My shelves are well-stocked, I make a menu each week with a variety of healthful options, I aim to do physical activity daily, and I still keep track of my calories. As for my teaching, I am no longer drowning in data, but rather making the connection between data collection from formative assessments to the mysterious and sometimes elusive skill of differentiation. This link is one that many teachers are missing as they work to meet the academic needs of all of their students. It is up to districts, even in these tough economic times, to provide teachers with the training they need to make the connection between data and teaching moves that result in learning. Only then is it fair to evaluate teachers' performance based on student outcomes.

In the meantime, I am looking forward to making data work for my waistline and, when I'm back in the classroom, the students that I serve.