A DC-based community advocacy group, The Finance Project, has released the latest in a series of reports that try to crack education's hardest nut: the costs and benefits of professional development (PD). This particular report, Inside the Black Box: School District Spending on Professional Development in Education, focuses on what districts are spending, with breakdowns by geographical region. In the Midwest, for example, districts report spending nearly $8,000 per teacher on PD each year, while in the Southwest, the reported figure is only $2,000.

While that funding discrepancy may appear gargantuan, the more telling story is how unreliable these figures probably are. With professional development funds coming at districts from all sides and no industry standard for defining, categorizing and capturing the effectiveness of these activities, there's almost no accountability for an educational area in which literally billions of dollars have been invested.