We were at the old Baltimore Sun offices on Calvert Street in early 2017 when then-Sun education reporter Erica L. Green yelled across the desk: “Where’s that casino money?”

It was a perennial question for those of us who closely follow school funding issues, but parents and teachers were asking it more frequently as Baltimore city schools were facing a huge $130 million funding gap.

So, we downloaded eight years of state budget documents and started to dig into the numbers.

While the casino money was, indeed, being used to fund education, it was largely supplanting existing funding streams, not adding to them.

Since casinos began pumping out cash for schools in 2010, the state of Maryland had lowered the percentage of the general fund dedicated to public schools. The state was now spending just 18 percent of its general fund on public K-12 education — down from 21 percent before the casinos opened.

Contacted about the matter, Gov. Larry Hogan’s spokesman Doug Mayer said no one had ever raised the issue with the administration.

We published our story, which renewed debate over the topic.

By the next legislative session, Democrats and Republicans alike were pushing various bills to add the money to school spending. Advocates, including the state’s influential teachers’ union, pushed for reform.

Hogan proposed legislation to create a “lockbox” to ensure the casino money was added to existing funds, which would increase state spending on public education by $4.4 billion over the next decade.

Democrats proposed a different route to roughly the same end, calling for a constitutional amendment to use the casino money to increase education funding beyond the levels required by a state formula.

The lockbox amendment called for a phase-in period and required that the casino revenue be added to other required education spending by July 1, 2022. The revenue is projected to be about $517 million a year by then.

The amendment proved wildly popular among Maryland voters.

In November, nearly 90 percent backed it at the ballot box, enshrining the policy in the Maryland Constitution.

— Luke Broadwater