"A typical classroom gets an average of five new students a year."

Student mobility - kids moving in and out of a school - is something teachers think about a lot, especially those who teach in poverty-stricken neighborhoods, where it can be a big problem. Undoubtedly the chief sufferers' are the youngsters who suddenly find themselves in a strange class where they have no idea what's going on. But getting a new student or two in the middle of the year is also hard on the other kids in the class and on the teachers. Until recently, however, there has been little information on the extent of the problem and few real efforts to solve it.

A recent study of student mobility in Chicago elementary schools, which is described in the latest issue of American Educator ("Kids, Schools Suffer from Revolving Door," Spring 1996), makes clear how serious the problem is. At one school of about 800 students, 170 new students enrolled between the beginning of school and January 31, and 198 left. In addition, 177 families brought children to be enrolled but transferred out before the children actually came to class. Of course, the problem is not this severe in most Chicago schools. Nevertheless, the study found that a majority of children -- three in five -- move from one school to another during their elementary school years; and nearly half of the moves take place during the school year. When researchers looked at the data from the school perspective, they found that "a typical classroom gets an average of five new students a year."

How does this affect the education that students in these schools are getting? It's pretty clear what problems the kids who transfer in are likely to have. As the American Educator article puts it, "For many transfer students, mobility is a vicious cycle: They're dropped into lessons that their previous school didn't prepare them for." Then, because they are "starting out behind in strange territory, many transfer students act out, making learning still harder." The long-term results are just what you might fear: The Chicago study found that "by fourth grade, students who had switched schools were, on average, four months behind students who had stayed in the [same] school." And the more often students change schools, the more devastating the effect on their achievement: "Students who had moved four or more times were, by sixth grade, a full year behind."

But even kids who never move are affected by the arrival of new students who do not know the material. Perhaps the teacher spends extra time with the new children, trying to catch them up, or perhaps she simplifies the curriculum so they can follow. Either way, the other students lose. And if there are two or three or four transfer students in the class -- and a couple of them turn out to be discipline problems -- the difficulties that come from their lack of preparation are multiplied many times.

What can be done? One approach the article suggests is to make sure parents are aware of how changing schools can affect their children. David Schuler, the president of an apartment owners' association in Rochester, New York, was appalled by the turnover rate among children in his apartment buildings. So he organized a successful campaign to educate parents and help them find housing within the attendance boundaries if they had to move. Schools and school districts can do the same thing. They can also relax their rules so students who have moved out of their school's attendance area can complete the year without changing schools -- a number of districts have already done this. And they can make sure that parents are aware of this flexibility. But useful though these approaches are, they can't really get to the heart of the problem.

What if students who moved from one school to another didn't have to face material that was totally unfamiliar? What if teachers knew that a fourth grader who came into class in January had studied certain topics in English? That's what would happen if we had a common curriculum, as they do in other industrialized nations with successful school systems. And it would be a boon not only for kids who move but for all students. Our free-and-easy approach to curriculum means that what fourth graders learn in a given subject can differ from school to school and even class to class. So teachers can never be sure what the students who enter their class know, and they have to waste precious time making sure that everybody is ready to start on the year's work.

The American Educator article says that some of the Chicago schools are aligning their curriculums to help ease the transition for transferring youngsters. They have the right idea. This is something we need to do for all our students.