Joy Pullmann of the Federalist delivers bad news to fans of Common Core.

Researchers the Obama administration funded to assist Common Core’s rollout recently found, to their surprise, that under Common Core U.S. student achievement has sunk.

“Contrary to our expectation, we found that [Common Core] had significant negative effects on 4th graders’ reading achievement during the 7 years after the adoption of the new standards, and had a significant negative effect on 8th graders’ math achievement 7 years after adoption based on analyses of NAEP composite scores,” the Center on Standards, Alignment, Instruction and Learning (C-SAIL) preliminary study said. “The size of these negative effects, however, was generally small.”

The study found not only lower student achievement since Common Core, but also performed data analysis suggesting students would have done better if Common Core had never existed. The achievement declines also grew worse over time, study coauthor Mengli Song told Chalkbeat, an education news website: “That’s a little troubling.”

Common Core is 640 pages of K-12 curriculum and testing mandates that nearly every state switched to between 2010 and 2013 under heavy federal pressure. President Obama, his education secretary Arne Duncan, and private financier Bill Gates promised the nation that overhauling what students learn and how it is measured would lead to student achievement gains.