Senate lawmakers recently took an important step when they set to work rewriting and improving the decade-old No Child Left Behind law. But along the way, as so often happens in Washington,  special interests lobbied hard for and won changes that dramatically weakened the bill that emerged from committee. If those revisions stand, the legislation would actually set us back — reverting to an era of lower expectations and less accountability in our schools, not more.

Most troubling is the stripping of essential language in the bill that would have required states to ensure that all schools have meaningful teacher evaluation systems. Too often, our teachers are reviewed inconsistently and subjectively.

We must identify our best teachers so they can serve as mentors and share best practices with other educators. They must be recognized and rewarded. Likewise, ineffective teachers must also be identified so they can be given the support they need to quickly improve their practice or move to a different profession. The problem is that most current evaluation systems don’t do this. In fact, they typically don’t even look at how well teachers are doing helping kids learn and neither recognize excellence nor identify problems. As a result, no one is helped — not the kids, not the adults.

The Senate bill, in its current form, would require new evaluation systems to be implemented in only the schools or districts that seek a specific kind of federal grant. That creates a two-tiered approach in which only a minority of students would be taught by teachers who benefit from the feedback and recognition that comes with good evaluations.

Fair questions are being raised about the role of the federal government in our schools. We don’t think Washington should script teacher evaluation systems. States and districts should work with stakeholders to develop these systems according to local needs and circumstances. It is appropriate — in fact it’s necessary — for the federal government to require that they be rigorous and transparent. Of course, local jurisdictions should determine some of the specifics. But, in all cases, teachers’ reviews should be based in significant part on whether their students are making expected academic gains.

There’s no doubt that teachers are our most valuable in-school resource. They matter way more than laptops or fancy buildings. Research from Stanford University shows an effective educator can generate three times the learning gains of an ineffective teacher. Knowing that, don’t we have an obligation to figure out who is excelling and who needs more help?

When Republicans and Democrats came together to craft No Child Left Behind, they created a landmark law that was by no means perfect but which spelled out very clearly that our nation would no longer tolerate low expectations for any children, no matter their skin color, ZIP code or family income.

One flaw in the law was the noble but difficult goal requiring that all children must be working on grade level by 2014. Senate lawmakers did the right thing by trying to amend that, but the final bill that emerged from committee was stripped of any real academic progress goals. That’s going too far.

The legislation as it is currently written allows states to set their own goals for student achievement. This will likely mean that some states may set high goals for kids, while others set low ones. It even means states might end up having different expectations for different subgroups of children. A great education ought to be a basic civil right for every child in America — no exceptions. The Senate bill, in its current form, does not live up to that ideal.

When the bill emerged from committee, StudentsFirst members sent 200,000 letters to lawmakers urging them to strengthen the bill. In one such letter, Meghan, a parent and former teacher, wrote about working in a school that had a strong evaluation system. “I am a better teacher because of this rigorous system. It is the key to having schools filled with excellent teachers, which is what we all ought to be working toward,” she wrote.

I hope lawmakers listen, if not to me and to Meghan, then to the children of our country who are depending on us to hold their schools accountable and ensure every one of them gets the great education they deserve.

Michelle Rhee is founder and CEO of StudentsFirst. She served as chancellor of Washington, D.C., schools from 2007 to 2010.