According to the RAND Corporation’s new study, the Gates Foundation just wasted a lot of money. Like, hundreds of millions.

Inspired by Obama’s education approach to weed out low-performing teachers, the Bill & Melinda Gates Foundation invested $212 million to help redesign the way teachers are evaluated in charter and public schools across California, Pennsylvania, Tennessee, and Florida. The improvements were minimal to none.

According to Chalkbeat, Gates’ contribution was part of a larger $575 million “Intensive Partnerships for Effective Teaching” reform during the 2009-10 and 2015-16 school years which called on principals to reconsider their recruitment, placement, and compensation practices. The program was also inspired by Thomas Kane who served as an economic advisor under the Clinton Administration.

But when RAND studied math and reading scores from before and after the reform, improvement was scarce with some schools left worse off.

“Dropout rates were not dramatically better than they were for similar sites that did not participate” in the program, the report found, The74 reports.

Minority and low-income students were a particular target, but in Hillsborough County, they were left with less effective teachers due to the program.

While teachers in the experimental districts initially backed the approach, they “were highly skeptical that the evaluation system was fair,” Chalkbeat reports.

Brown University professor Matt Kraft, who studies education reform, criticized the program as “being limited in its potential.”

The Gates Foundation has since ditched the approach to focus on improving curriculum instead.

“We have taken these lessons to heart, and they are reflected in the work that we’re doing moving forward,” the Foundation’s spokesman Allan Golston admitted. (RELATED: Bill Gates Drops $1.7 Billion To Reform Public Schools)

“Microsoft’s Bill Gates gave to three Democratic congressmen,” The Washington Post reports. Open Secrets lists several lawmakers who received his contributions.

The RAND Corporation is a nonprofit think tank devoted to solutions on public policy.