The issue, according to state leaders, is how best to measure a school in the Seattle area against a school in Spokane or some other part of the state. Critics of the grading plan say it can't be done.
Protestors arrived in Olympia on Wednesday to make their feelings known about plan, known as Healthy Kids and Healthy Schools.
State Sen. Steve Litzow, R-Mercer Island, is behind the bill.
"We grade our kids this way," he said. "Everybody understands A to F. That's the whole point."
The bill would give every public school in Washington a letter grade based on student performance, test results and graduation rates. Schools that get high marks would receive more money
"It's simple and understandable," Litzow said. "That school is doing really well for its students or it's not."
But many people who work with students say Litzow's math doesn't add up. Local elementary school principal Ron Sisson spent years as a teacher in Los Angeles, where a similar system was in play.
"The issue that it created was that teachers were very selective about what students were in their class because they knew it was going to be a fiscal hit," Sisson said.
A fiscal hit is one thing, but a failing grade is another.
Janis Aimee doesn't see how you can compare her grandson's elementary school in Olympia to a school in a more rural area, such as Enumclaw.
"I don't think you can make those kind of judgements. This school in particular serves a lot of homeless children," she said. "Statistically, those kids tend to fall behind and so teachers end up playing catch up."
There is always debate about how best to hold teachers accountable, but many educators say this new bill is not the solution.
"The theory is they're going to reward high-performing schools with more money while really denying the support some of our neediest schools need," said Mary Lindquist, president of the Washington Education Association.
If the bill passes it would go into effect later this year, but there's no companion bill in the house, which may make for an uphill battle.