So, it turns out that Michelle Rhee knew what she was doing. Stanford’s Tom Dee and the University of Virginia’s Jim Wyckoff have just published an important study on Washington D.C.’s controversial teacher-evaluation system. They find that the IMPACT system launched by former chancellor Michelle Rhee appears to boost teacher effectiveness and also makes it more likely that low-performing teachers will depart. Deservedly, he study got a lot of attention yesterday, including in the New York Times and the Washington Post.
Making clever use of regression-discontinuity design, the authors note that IMPACT appears to aid students both by “avoiding the career-long retention of the lowest-performing teachers and through broad increases in teacher performance.”
IMPACT is a program, not a statute: This means that DCPS has been able to readily and repeatedly tweak the system, year over year (and even sometimes during the year). The evaluation model is not set in stone and needn’t apply to a slew of districts with various needs; it is designed for DCPS. Efforts to legislate statewide teacher-evaluation systems, of the kind championed by the Obama administration in Race to the Top and as a condition for No Child Left Behind waivers, may be a whole different kettle of fish
Talent and Technology: Over time, DCPS has recruited and assembled a remarkable, large, and sustained team to design and implement IMPACT. They became a magnet for talent on this precisely because they were a national leader. They’ve tapped top-shelf advisers, worked assiduously to address educator concerns, and taken pains to explain the system clearly and accessibly to educators. This has been a big expense, in a district of just 45,000. It also turns out that many of the data systems in place in DCPS were inadequate for IMPACT’s needs. The district essentially had to build a parallel personnel data system in order to handle IMPACT. Indeed, many big school districts may lack even the basic information technology needed to make an IMPACT-style system work.
The results on IMPACT are heartening. But it would be a mistake to allow reassuring results to serve as a justification for half-baked efforts or one-size-fits-all teacher-evaluation statutes. Doing so runs the risk of encouraging inept efforts to scale a promising possibility.