Take, for example, George Hall Elementary School, which serves a poor, isolated neighborhood in Mobile, Ala. All its students qualify for the federal student lunch program, and all are African-American. In 2004, George Hall was once one of the lowest-performing schools in the city; today it is among the top-performing schools in the state, outperforming many of Alabama's most affluent schools.

What does George Hall--and the other schools I have studied--do to be so successful? Each school is exemplary in its own way. Some are small, some large, some rural, some urban, some suburban, some elementary, and some secondary, but they all share the same basic approach. They:

Focus on what students need to know and be able to do in order to be ready for college or career training when they leave high school.

Help the faculty collaborate in order to teach.

Assess frequently to see who has learned the material and who needs extra help.

Study class, grade, and school assessment data to find patterns of instruction in order to improve.

Deliberately build relationships between students and staff and among staff so that students trust teachers enough to learn from them and teachers trust each other enough to work together.

This list seems almost too simple, but it gets at the core of how schools should operate and avoids all the fads and fashions that too often overwhelm the field of education. As simple as this formula is, it represents a very different way of organizing schools. Most schools are organized around individual classroom teachers teaching in isolation. This means that students are highly dependent on which teachers they get.

A good teacher means a good year of learning; a not-so-good teacher can mean falling behind. Two or three bad teachers in a row can be a disaster for a student, particularly one whose family is not able to compensate for weak instruction.

The schools I have been studying--I call them "It's Being Done" schools--do not leave teachers to teach in isolation. Their leaders and staff know that no individual teacher can possibly know enough to be able to help every single student and that only by pooling their knowledge and skill can teachers reach everyone.

It turns out, however, that it isn't so easy to collaborate in these ways. Teachers themselves need teachers to help them work in ways that are best for students. That means that principals are critical to improving schools because, as schools' head teachers, they are the ones who can focus a school's efforts to help all children and help teachers learn to work in these new ways.

The big picture? We know what is necessary to make schools work for all kids, and at least some people know how to do get the job done. Now we just have to spread that knowledge around.