Tennessee is at it again! The Volunteer State, known for its strong policies around teacher prep and teacher evaluation, is once again offering up its data. A new report shares the holy grail of measuring teacher prep programs: looking at what their teachers accomplish in the classroom.

This analysis from Jack Powers in Tennessee's Office of Research and Education Accountability examines outcomes for three groups of teacher preparation programs: traditional public programs, traditional private programs, and alternative route programs (here referred to as "education-related organizations"). Unfortunately, unlike their teacher prep program report cards, which have allowed for some compelling analysis, they don't name individual programs.

When new teachers from each of these three groups reach the classroom, their average evaluation ratings and observation scores look remarkably similar. A slightly higher proportion of teachers from traditional programs earn the top two observation scores (20 percent versus 17 percent of alternative route programs).

However, value-added scores (from Tennessee's TVAAS system) are substantially higher for teachers coming from alternative route programs like Teach For America. Only about a quarter of traditionally prepared teachers are in the highest categories on this metric, comparing unfavorably with more than 40 percent of teachers from alternative routes.

Two takeaways are clear from this report: there's something in the water of those alt-route programs that their traditional program peers should drink in and more states should be doing this kind of outcome-based analysis.