If Suyin So had more funding, she would increase small group instruction, provide more music classes, and offer a language at her charter school in Queens. But first, she’d deal with the pipe that burst in a special education classroom this year.

“We’re contending with, is the boiler going to blow and who’s going to fix that?” said So, the founder and executive director of Central Queens Academy. Recently, she added, “I’ve learned way more about construction than about instruction.”

So is one of many hoping for increased charter school funding in the state budget this year. While district school per-student funding has increased by $2,113 since 2010 in New York City, charter schools have seen a $350 per-student increase, according to Families for Excellent Schools, the pro-charter group that organized a rally around the issue on Wednesday in Albany.

That doesn’t necessarily mean all charter schools have had less to spend on students than district schools. But the bulk of public funding for charter schools has been held nearly constant for five years. Advocates hope that will change this year, since the governor proposed lifting the freeze in New York City in his executive budget.

But why was the funding freeze there to begin with? Why change it now? And how has it affected charter schools?

Here’s what you need to know.

What’s the funding freeze?

Under state law, as district school funding increases or decreases, so should charter school funding. (The charter figure lags by two years.) But the governor and legislature froze the number for charter schools at the end of the recession for 2009-10 and then again in 2010-11. The level of funding has held at the 2010-11 level ever since.

In the first years of the freeze, funding increases did not differ dramatically between district schools and charter schools. Some charter advocates were grateful that their funding remained constant during tough budgetary times.

But as the economy improved, district schools began receiving more funds, including from a new city teacher contract that upped teacher salaries. Charter schools got funding boosts in lump sums from the state, but overall, district school funding in New York City increased at six times the rate of charter school funding, according to FES.

Now, charter school advocates want to return to a formula that allows charter funding to increase as district school funds do.

So, have charter schools had less to spend on students?

It depends. Last summer, the city’s Independent Budget Office said although the city has increased funding for district schools more than for charter schools, the funding they receive is nearly identical — at least for the charter schools that operate in district buildings.

When those services, including maintenance and security costs, are taken into account, co-located charter schools received only $29 per student less than district schools in 2014-2015, according to the IBO.

“We say it’s essentially the same,” said Ray Domanico, the IBO’s research director.“Twenty-nine dollars is really a pretty meaningless difference.”

Charter schools that pay for their own space, though, received almost $3,000 less per student in funding than district schools, according to the IBO. All told, the city’s traditional public schools received an average of $17,928 per student in 2014-15, while co-located charter schools received $17,899 and charter schools in private space received $15,014.

(Advocacy groups, including FES and the Northeast Charter Schools Network, have disputed the IBO’s findings and questioned its methodology.)

As the city’s teachers union is quick to point out, charter schools can also raise money through private fundraising. New or expanding charter schools can now also apply for money to help pay for private space — further reducing that gap for schools that qualify. Central Queens Academy, which rents its own space and opened in 2012, gets that funding for some, but not all, of its students.

Why do charter advocates care about this now?

Charter advocates have been pushing to unfreeze the per-student funding formula for years, but it didn’t make it into Gov. Cuomo’s proposal or the final budget deal last year.

The funding boost would also provide an immediate benefit to all city charter schools, unlike the rent assistance, and would come as education spending continues to rise at a fast clip. From 2009 to 2014, district schools increased general education spending by $1,376 per student, according to the IBO.

What is the governor proposing?

The governor proposed both a lump sum of $27 million for charter schools and for charter school funding to parallel district school funding in New York City.

The funding formula is already set to unfreeze for the entire state next year, which means the governor’s proposal would “jumpstart” the process for New York City, said Andrea Rogers, a senior policy director at Northeast Charter Schools Network.