Now that the philanthropic Bill and Melinda Gates have announced they are divorcing after 27 years of marriage, let’s look at the controversial investments they made together to reform K-12 public education — and how well those worked out.

Together, the two have been among the most generous philanthropists on the planet, spending more over the past few decades on global health than many countries do and more on U.S. education reform than any of the other wealthy Americans who have tried to impact K-12 education with their personal fortunes.

The Bill & Melinda Gates Foundation has spent billions of dollars on numerous education projections — such as creating small high schools, writing and implementing the Common Core State Standards, evaluating teachers by standardized test scores — and the couple has had enormous influence on what happened in classrooms across the country.

Their philanthropy, especially in the school reform area, has been at the center of a national debate about whether it serves democracy when wealthy people can use their own money to drive public policy and fund their pet education projects. The foundation’s financial backing of some controversial priorities of the Obama administration’s Education Department put the couple at the center of this national conversation.

Critics have said that many of the foundation’s key education projects have harmed public schools because they were unworkable from the start and consumed resources that could have been better spent.

But you don’t have to go any further than the Gateses themselves to learn that some of the billions of dollars they put into public education reform efforts did not go as well as they liked.

In 2013, Bill Gates said, “It would be great if our education stuff worked. But that we won’t know for probably a decade.”

It didn’t take 10 years for them and their foundation to acknowledge that key education investments didn’t turn out as well as they hoped.

In the foundation’s 2020 annual letter, Melinda Gates said: “The fact that progress has been harder to achieve than we hoped is no reason to give up, though. Just the opposite.”

That same annual letter had a rather remarkable statement from Melinda Gates about the role of the wealthy in education policy, given her and husband’s role in it:

We certainly understand why many people are skeptical about the idea of billionaire philanthropists designing classroom innovations or setting education policy. Frankly, we are, too. Bill and I have always been clear that our role isn’t to generate ideas ourselves; it’s to support innovation driven by people who have spent their careers working in education: teachers, administrators, researchers, and community leaders.

Bill and Melinda Gates have spent billions to shape education policy. Now, they say, they’re ‘skeptical’ of ‘billionaires’ trying to do just that.

The Gates Foundation began its first big effort in education reform about two decades ago with what it said was a $650 million investment to break large, failing high schools into smaller schools.

There was a focus in education at the time that small schools worked better for students — especially those at risk — than large ones, and foundation money went to big high schools around the country, including in New York City, to break them up into smaller ones. Some schools worked and some didn’t, but the Gateses announced in the foundation’s 2009 annual letter that the results weren’t good enough and they were moving on:

Many of the small schools that we invested in did not improve students’ achievement in any significant way. These tended to be the schools that did not take radical steps to change the culture, such as allowing the principal to pick the team of teachers or change the curriculum. We had less success trying to change an existing school than helping to create a new school. Even so, many schools had higher attendance and graduation rates than their peers. While we were pleased with these improvements, we are trying to raise college-ready graduation rates, and in most cases, we fell short.

The foundation was instrumental in the Common Core State Standards initiative, a set of standards in English language arts and math promoted by the Obama administration that were intended to be used by all public schools.

The Gateses funded the development, implementation and promotion of the Common Core standards, which were initially adopted by most states in the early 2010′s on a bipartisan basis. Districts spent a lot of money to bring in new materials and teacher training, but the Core became controversial, in part because of the rush to get it into schools and because of what many states said was federal coercion to adopt it. Many states later backed away or rebranded them.

By 2013, Bill Gates conceded that the initiative had not succeeded as he had expected, and in 2016, Sue Desmond-Hellmann, then the chief executive officer of the foundation, wrote this in an annual letter about the foundation’s investment in the Common Core:

Unfortunately, our foundation underestimated the level of resources and support required for our public education systems to be well-equipped to implement the standards. We missed an early opportunity to sufficiently engage educators — particularly teachers — but also parents and communities so that the benefits of the standards could take flight from the beginning.

The couple also championed teacher evaluation systems that were based on student scores on high-stakes standardized tests — a method that assessment experts warned against using. Those experts included the American Statistical Association, the largest organization in the United States representing statisticians and related professionals, as well as the National Academy of Sciences’ Board on Testing and Assessment.

The foundation distributed hundreds of millions of dollars among three public school systems and four charter management organizations to develop and implement teacher assessment systems that incorporated student standardized test scores. School systems and charter organizations that took the foundation’s money were required to use public funds on the project, too.

Bill Gates spent hundreds of millions of dollars to improve teaching. New report says it was a bust.

A 2018 report concluded that the teacher evaluation project had failed to achieve its goal of improving student achievement in any significant way. It said in part:

Overall, the initiative did not achieve its stated goals for students, particularly LIM [low-income minority] students. By the end of 2014-2015, student outcomes were not dramatically better than outcomes in similar sites that did not participate in the IP [Intensive Partnerships] initiative. Furthermore, in the sites where these analyses could be conducted, we did not find improvement in the effectiveness of newly hired teachers relative to experienced teachers; we found very few instances of improvement in the effectiveness of the teaching force overall; we found no evidence that LIM students had greater access than non-LIM students to effective teaching; and we found no increase in the retention of effective teachers, although we did find declines in the retention of ineffective teachers in most sites.

By 2020, the couple acknowledged the difficulties of education philanthropy, with Bill Gates saying:

Rather than focus on one-size-fits-all solutions, our foundation wants to create opportunities for schools to learn from each other. What worked at North-Grand won’t work everywhere. That’s why it’s important that other schools in other networks share their success stories, too.

As the foundation continues to fund numerous education projects, its 2021 annual letter, issued during the coronavirus pandemic, concentrated on health initiatives, connecting them to its work in U.S. education reform:

We’re also addressing the pandemic’s disproportionate impact on people of color in other ways, including through our foundation’s U.S. education work. We’re concerned about students falling behind at all levels (when schools closed last spring, the average student lost months of learning), but we’re especially troubled that COVID-19 could exacerbate long-standing barriers to higher education, particularly for students who are Black, Latino, or from low-income households. Median lifetime earnings of college graduates are twice those of high school graduates, so the stakes for these young people are high. To help students navigate COVID-19 roadblocks, our foundation expanded our partnerships with three organizations that have a proven track record of using digital tools to help students stay on the path to a college degree. We think the models and approaches these organizations are honing now will continue to expand opportunities for students post-pandemic, too.