T.C. Williams High School in Virginia has many high achievers, but it’s a “persistently low-achieving school.” It’s an “unfriendly wake-up call,” writes English teacher Patrick Welsh in the Washington Post.

T.C. Williams has always been proud of its student achievement and its diverse community. But as the demographics of the school shifted over the past 25 years and low-income students — many of them minorities and immigrants — began to outnumber middle-class kids, one thing that didn’t change was the way the school thought about its students. Even though we knew better, many of us — both teachers and administrators — acted as if all our students came to school with basic reading and math skills and had a parent at home actively supervising their education. The stragglers could do the work, we insisted, if they were in a room full of other kids who could do the work, too. The school definitely did not want to create tracking classes, in which kids are separated according to ability, or anything that could resemble ethnic or class-based segregation.

Instead of zeroing in on the relatively small number of students who came to us unprepared and needed a great deal of help to catch up, we opted for appearances. The school mixed kids of different academic levels into the same classes in hopes that the best students would pull up those on the bottom. We also continued passing kids through the system, whether they had learned the skills they needed or not. Gary Thomas says many students enter T.C. Williams not knowing how to add or subtract without a calculator, and even the better students do not understand fractions.

A task force suggested creating an alternative school for challenged students, but a “small but vocal cadre of short-sighted community activists,” mostly black, saw it as “a ruse to bring back segregation.” So nothing happened.

The school’s scores also are lowered because it enrolls newly arrived 18- to 20-year-old immigrants who speak little English, instead of sending them to an adult program tailored to their needs.

Because of the low-achieving label, T.C. Williams will submit a detailed plan for improvement. At a dinner, the superintendent “opened the floor for the most honest discussion I have heard in all my years at the school.”

One by one, teachers walked up to two microphones and addressed the problems — and solutions — they saw at T.C.: the lack of clear, consistent discipline; kids roaming the halls freely during class; the failure to curb cellphone and iPod use; the need to identify and focus on those students who are woefully behind in reading and math.

Under Arne Duncan’s revision of No Child Left Behind, schools like T.C. Williams would have to report scores by race, income level, disability status, etc., but wouldn’t face sanctions for not helping hard-to-educate students achieve. There are benefits in reducing the tyranny of test scores, but there will be fewer wake-up calls for schools where some kids are doing great and some are not.