The initiative, which began in 2009, was rolled out in three school districts and four charter school networks in California, Arkansas, Florida, and Pennsylvania. Called the Intensive Partnerships for Effective Teaching initiative, it sought to improve teacher effectiveness, by “changing the way schools recruit, retain, and reward teachers.”

Improving teacher effectiveness, it hoped, would in turn improve the quality of the education the students received, thereby increasing graduation rates and college acceptance for low-income and minority students.

Over the course of the several-year project, the Gates Foundation contributed more than $200 million into the close to $1 billion initiative.

The Gates Foundation selected nonprofit policy think tank RAND at the start of the initiative in 2009 to evaluate the effectiveness of the project, measuring whether it improved outcomes for students.

But according to a new report, RAND found that by 2015, “student achievement, access to effective teaching, and dropout rates were not dramatically better” as compared to schools that were not participants.

The Foundation has acknowledged the shortcomings of the initiative, with Gates himself noting last year that they will “no longer directly invest in teacher evaluation.” Instead, the Gates Foundation will “continue to gather data on the impact of these systems and encourage the use of all of those tools that help teachers improve their practice.”

Allan Golston, who runs the Foundation’s U.S. education initiatives echoed this in a statement, saying that they have “taken these lessons to heart, and they are reflected in the work that we’re doing moving forward, where we will support the efforts of networks of schools to identify locally driven solutions, rooted in a commitment to the use of evidence and data to improve student outcomes in middle and high school.”