( CNN ) -- The nation 's suburban schools added 3.4 million students to their rolls over the past 15 years -- and nearly all of them were minorities , according to a study released Tuesday . Jean Bonner teaches fourth-graders last month at Middleburg Elementary in suburban Washington . Yet the new arrivals resulted in only a modest increase in the individual schools ' racial and ethnic diversity , the study said . `` The school districts look like they are more diverse , but within your school districts , if the whites are in one school , the blacks in a different school and the Hispanics in yet a different school , it does n't necessarily mean the suburban whites have more black and Hispanic classmates -- because they do n't go to the same school , '' said Richard Fry , senior research associate at the Pew Hispanic Center in Washington , who wrote the report . Using federal government data , Fry found that minority students made up 99 percent of the increase in suburban school enrollment between the 1993-94 and 2006-07 school years . During that time , the student body at the nation 's suburban schools went from 72 percent white to 59 percent white ; from 12 percent black to 15 percent black ; from 11 percent Hispanic to 20 percent Hispanic ; and from 5 percent Asian to 6 percent Asian . The diversity , however , is not reflected at the individual school level . For example , in 2006-07 , the typical white suburban student attended a school whose student body was 75 percent white , down from 83 percent white in 1993-94 , Fry wrote . `` So at a time when the white share of student enrollment in suburban school districts was falling by 13 percentage points , the exposure of the typical white suburban student to minority students in his or her own school was growing by a little more than half that much -- or 8 percentage points , '' the report said . From another point of view , the typical black suburban student attended a school in 2006-07 that was 34 percent white , down from 43 percent white in 1993-94 . But Latino suburban students tended to become more segregated over the same time period -- in 2006-07 , the typical such student was in a school that was 49 percent Latino , versus 42 percent Latino in 1993-94 . Suburban schools accounted for most of the change in demographics , according to the study , accounting for two-thirds of the 5.1 million increase in the number of students nationwide over that time period . City schools tended to be more segregated than their suburban counterparts , the study said , with the typical urban black student attending a school with 60 percent black enrollees ; and the typical Latino student attending a school with 63 percent Latino enrollment . Minority students in rural areas and in towns tended to be more exposed to whites than were their suburban counterparts . The typical black student in a town or rural area attended a school where whites composed 47 percent of the student body and blacks 44 percent . The typical Latino student in a town or rural area attended a school where whites made up 43 percent of the student body , and Latinos made up 47 percent . Asians in suburban schools saw only a slight uptick in isolation -- from 23 percent Asian to 24 percent Asian over the time period . However , `` white students are n't going to school with as many black and Hispanic students as the aggregate school district enrollment numbers indicate , '' Fry said in a telephone interview . School diversity has long been considered an important marker of racial equality in education . `` When students of different racial/ethnic backgrounds do not attend the same schools , the potential exists that they also may not attend the same type of schools , i.e. , schools of similar quality and level of resources , '' Fry wrote . `` Racial differences in school quality ... can not exist if schools are racially balanced . '' The study identified the nation 's most-segregated suburban school district as Maywood-Melrose Park-Broadview 89 School District in suburban Chicago , Illinois , based on its `` dissimilarity index '' of 0.79 . That index means that 79 percent of the district 's minority students would have to be moved to different schools in order for the schools ' student bodies to mirror the ethnic makeup of the surrounding population , he said . The 0.74 figure for suburban Atlanta , Georgia 's , DeKalb County means `` you would have to move about three-quarters of DeKalb County 's black students to a different school '' in order to get racial balance , he said . Calls to school superintendents in both districts were not immediately returned . `` The suburbs seem to have grown a lot more diverse , '' Fry concluded . `` The place you 'd expect to see it is among kids . But when you actually look at where kids go to school , it 's not clear that white kids are going to school with a whole bunch more different classmates than they used to -- a little bit more , but not as much as the aggregate measures would suggest . ''
Minorities made up 99 percent of increase in suburban school rolls , study says . Diversity rose , but typical white suburban students attend 75 percent-white schools . Expert : Racial differences in schools `` can not exist if schools are racially balanced '' Most-segregated suburban district lies in suburban Chicago , Illinois , study finds .