From a blog post at Diane Ravitich’s site:
An analogy to the Gold Rush may be useful here: The claim stakers are the federal government and philanthropies that have staked out the Common Core for public policy. To work that stake, they incentivize states and school districts to mine the Common Core and get higher measured achievement. To do so, the miners need equipment. The vendors who sell the equipment profit in the short term, even if their tools rarely enable the miners to get the sought-after results. In essence, those who set directions for the Common Core and those who provided resources for its implementation have benefitted, even as potential benefits to schools, educators, and students are elusive, and the entire claim may ultimately be empty.