Mb. Justice Stewakt
delivered the opinion of the Court.
We granted certiorari in this case, as in No. 70-130, United States v. Scotland Neck City Board of Education, post, p. 484, to consider the circumstances under which a federal court may enjoin state or local officials from carving out a new school district from an existing district that has not yet completed the process of dismantling a system of enforced racial segregation. We did not address ourselves-to this rather narrow question in Swann v. Charlotte-Mecklenburg Board of Education, 402 U. S. 1, and its companion cases decided last Term, but the problem has confronted other federal courts in one form or another on numerous occasions in recent years. Here, as in Scotland Neck, the Court of Appeals, reversed a district court decision, enjoining the. creation of a new schpol district. 442 F. 2d 570. We conclude that the Court of Appeals erred in its interpretation of the legal principles applicable ini cases such as these, and that the District Court’s order was proper in the circumstances of this case.
I
- The City of Emporia lies near the center of Greens-ville County, Virginia, a largely rural area located on the North Carolina border. Until 1967, Emporia was a “town” under Virginia law, which meant that it was a part of .the surrounding county for practically all purposes, including the purpose of providing public education for children residing in the county.
In 1967, Emporia, apparently dissatisfied with the county’s allocation of revenues from the newly enacted state sales tax, successfully sought designation as a “city of the second class.” As such, it became politically independent from, the surrounding county, and undertook a separate obligation under state law to provide free public schooling to children residing within its borders. To fulfill this responsibility, Emporia at first sought the county’s agreement to continue operating the school system on virtually the same basis as before, with Emporia sharing in the administration as well as the financing of the schools. When the county officials refused to enter into an arrangement of- this kind, Em-poria agréed to a contract whereby the county , would continue to educate students residing in. the city in exchange for Emporia’s payment of a specified- share of the total cost of the system. Under this agreement, signed in April 1968, Emporia had a formal voice in the administration of the schools only through its participation in the selection of a superintendent. . The city and county were designated as a single school “division” by the State Board of Education, and this arrangement was still in effect at the time of the District Court’s order challenged in this case.
This lawsuit began in 1965, when a complaint was filed on behalf of Negro children seeking an end to state-enforced racial segregation in the Greensville County school system. Prior to 1965, the elementary and high. schools located in Emporia served all white children in the county, while Negro children throughout the county were assigned to a single high school or one of four elementary schools, all but one of which were located outside the Emporia town boundary. In January 1966, the District Court approved a so-called “freedom of choice” plan that had been adopted by the county in April of the previous year. Wright v. School Board of Greensville County, 252 F. Supp. 378. No white students ever attended the Negro schools under this plan, and in the 1968-1969 school year only 98 of the county’s 2,510 Negro students attended white schools. The school faculties remained completely segregated.
Following our decision in Green v. County School Board, 391 U. S. 430, holding that a freedom-of-choice plan was an unacceptable method of desegregation where it failed “to provide meaningful. assurance of prompt and effective disestablishment of a dual system,” id., at 438, the petitioners filed a motion for further relief. The District Court ordered the county to demonstrate its compliance with the holding in Green, or to submit a plan designed to bring the schools into compliance. After various delays, during which the freedom-of-choice sys-tern remained in effect, the county submitted two alternative plans. The first would have preserved the existing system with slight modifications, arid the second would have assigned students to schools on the basis of curricular choices or standardized test, scores. The District Court promptly rejected the first of these proposals, and took the second under advisement. Meanwhile, the petitioners submitted their own proposal, under which all children enrolled in a particular grade level would be as- , signed to the same school, thus eliminating any possibility ■ of racial bias in pupil assignments. Following an eviden-tiary hearing on June 23, Í969, the District Court rejected the county’s alternative, plan, finding that it would “substitute . . . one segregated school system for another segregated school system.” . By an order dated June 25, the court ordered the county to implement the plan submitted by the petitioners, referred to by the parties as the “pairing” plan, as of the start of the 1969-^-1970 school year.
' Two weeks after the District Court entered its decree, the Emporia City Council sent a letter to the county Board of Supervisors announcing the city’s intention to operate a separate school system beginning in September. The letter stated that an “in-depth study and analysis of the directed school arrangement reflects a totally .unacceptable situation to the Citizens and City Council of the City of Emporia.” It asked that thé 1968 city-county agreement be terminated by mutual consent, and that title to school property located within Emporia be transferred tó' the city. The letter further advised that children residing in the county would be permitted to enroll in the city schools on a tuition . basis. At no time during this period did the city officials meet with the County council or school board ..to discuss the implementation of the pairing decree, nor did they inform the District Court of their intentions with respect to the separate school system.
The county school board refused either to terminate the existing agreement or to transfer school buildings, to Emporia, citing its belief that Emporia’s proposed action was “not in the best interest of the children in Greensville County.” The City Council and the City School Board nevertheless continued to take steps toward implementing the separate system throughout the month of July. Notices were circulated inviting parents to register their children in the city system, and a-request was made to the State Board of Education to certify Emporia as a separate school division. This request was tabled, by the State Board- at its August meeting, “in light of matters pending in the federal court.”
According to figures later supplied to the District Court, there were 3,759 children enrolled, in the unitary system contemplated by the desegregation decree, of whom 66% were Negro and 34% were white. Had Emporia established a separate school system, 1^123 of these stüdents would have attended the city schools, of whom 48% were white. It is undisputed that the city proposed to operate its own schools on a unitary basis, with all children enrolled in any particular gradé attending: the same school.
On August 1, 1969, the petitioners filed a supplemental complaint naming the members of the Emporia City Council and the City School Board as additional parties defendant, and seeking to enjoin them from withdrawing Emporia children from the county schools. At the conclusion of a hearing on August 8, the District Court found that the. establishment of a separate school - system by the city would constitute “an impermissible interference, with and frustration of” its order of June 25, and preliminarily enjoined the respondents from taking “any.action which would interfere in any manner whatsoever with the implementation of the Court’s order heretofore entered. ...”
The schools opened in September under the páiring order, while Emporia continued to work' out detailed plans and budget estimates for a separate, school system in the hope that the District Court would allow its implementation during the following school year. At a further hearing in December, the ■ respondents presented an expert witness to testify as to the educational advantages of the proposed city system, and asked that the preliminary injunction be dissolved. On March 2, 1970, the District Court entered a. memorandum opinion and order denying the respondents’ motion and making the injunction permanent. 309 F. Supp. 671. The Court of Appeals for the Fourth Circuit reversed, 442 F. 2d 570, but stayed its marídate pending action by this Court on a petition for certiorari, which we granted. 404 U. S. 82Ó. . o
II
Emporia takes the position’that since it is a separate political jurisdiction entitled under state law to establish a school system independent of the county, its action may be enjoined only upon a finding either that the state law under which it acted is invalid, that the boundaries of the . city are drawn so as to exclude Negroes, or that thé disparity of the racial balance of the city and county schools of itself violates the Constitution. As we read its opinion, the District. Court made no such findings; nor do we.
. The constitutional violation that formed the predicate for the District Court’s action was the enforcement until 1969 of racial segregation in a public school system of which Emporia had always been a part. That finding has not been challenged, nor has Emporia questioned the propriety of the “pairing” order of June 25, 1969, which was designed to remedy the condition that offended the Constitution. Both before and after it became a city, Emporia educated its children in the county schools. Only when it became clear — 15 years after our decision in Brown v. Board of Education, 347 U. S. 483 — that segregation in the county system was finally to be abolished, did Emporia attempt to take its children out of the county system. Under these circumstances, the power of the District Court to enjoin Emporia’s withdrawal from that system need not rest, upon an independent constitutional violation. The court’s remedial power was invoked on the basis of a finding that the dual school system violated the Constitution, and since the city and the county constituted but one unit for the purpose of student assignments during the entire time that the dual system was maintained, they were properly treated as a single unit for the purpose of dismantling that system.
In Green v. County School Board, 391 U. S. 430, the issue was whether the school board’s adoption of a “freedom of choice” plan constituted adequate compliance with the mandate of Brown v. Board of Education, 349 U. S. 294 (Brown II). We did not hold that a freedom-of-choice plan is of itself unconstitutional. Rather, we decided that any plan is “unacceptable” where it “fails to provide meaningful assurance of prompt and effective disestablishment of a dual system. . . .” 391 U. S., at 438. In Monroe v. Board of Commissioners, 391 U. S. 450, we applied the same principle in rejecting a “free transfer” plan adopted by the school board as a method of desegregation:
“We do not hold that ‘free transfer’ can have no place in a desegregation plan. But like ‘freedom of choice,’ if it cannot be shown that such a plan will further rather than delay conversion to a unitary, nonracial, nondiscriminatory school system, it must be held unacceptable.” Id., at 459.
The effect of Emporia’s proposal was to erect new boundary lines for the purpose of school attendance in a district where no such lines had previously existed, and where a dual school system had long flourished. Under the principles of Green and Monroe, such a proposal must be judged according to whether it hinders or furthers the process of school desegregation. If the proposal would impede the dismantling of the dual system, then a district court, in the exercise of its remedial discretion, may enjoin it from being carried out.
The Court of Appeals apparently did not believe this case to be governed by the principles of Green and Monroe, It held that the question whether new school district boundaries should be permitted in areas with a history of state-enforced racial segregation is to be resolved in terms of the “dominant purpose of [the] boundary realignment.”
“If the creation of a new school district is designed . to further the aim of providing quality education and is attended secondarily by a modification of the racial balance, short of resegregation, the federal courts should not interfere. If, however, the primary purpose for creating a new school district is to retain as much of separation of the races as possible, the state has violated its affirmative constitutional duty to end state supported school segregation.” 442 F. 2d, at 572.
Although the District Court had found that “in a sense, race was a factor in the city’s decision to secede,” 309 F. Supp., at 680, the Court of Appeals found that the primary purpose of Emporia’s action was “benign,” and was not “merely a cover-up” for racial discrimination. 442 F. 2d, at 574.
This “dominant purpose” test finds no precedent in our decisions. It is true that where an action by school authorities is motivated by a demonstrated discriminatory purpose, the existence of that purpose may add to the discriminatory effect of the action by intensify^ ing the stigma of implied racial inferiority. And where a school board offers nonracial justifications for a plan that is less effective than other alternatives for dismantling a dual school system, a demonstrated racial purpose may be taken into consideration in determining the weight to be given to the proffered justification. Cf. Green, supra, at 439. But as we said in Palmer v. Thompson, 403 U. S. 217, 225, it “is difficult or impossible for any court to determine.the ‘sole’ or ‘dominant’ motivation behind the choices of a group of legislators,” and the same, may be said of the choices of a school board. In addition, an inquiry into the “dominant” motivation of school authorities is as irrelevant as it is fruitless. The mandate of Brown II was to desegregate schools, and we have said that “[t]he measure of any desegregation plan is its effectiveness.” Davis v. School Commissioners of Mobile County, 402 U. S. 33, 37. Thus, we have focused upon the effect — not the purposé or motivation — of a school board’s action in determining whether it is a permissible method of dismantling a dual system. The existence of a permissible purpose cannot süstain an action that has an impermissible effect.
The reasoning of the Court of Appeals in this case is at odds with that of other federal courts that have held that splinter school districts may not be created “where the effect — to say nothing of the purpose: — of-the secession has a substantial adverse effect on desegregation of the county school district.” Lee v. Macon County Board of Education, 448 F. 2d 746, 752. See also Stout v. Jefferson County Board of Education, 448 F. 2d 403, 404; Haney v. County Board of Education, 410 F. 2d 920, 924; Burleson v. County Board of Election Commissioners, 308 F. Supp. 352, 356,. aff’d, 432 F. 2d 1356; Aytch v. Mitchell, 320 F. Supp. 1372, 1377. Though the purpose of- the new school districts was .found to be discriminatory in many of these cases, the courts’ holdings rested not on motivation or purpose, but on- the effect of the action upon the dismantling of the dual school, systems involved. That was the focus of the District Court in this case, and we hold that its approach was proper.
in
The basis for the District Court’s ruling was its conclusion that if Emporia were allowed to establish an independent system, Negroes remaining in the county schools would be deprived of what Brown II promised them: a school system in which all vestiges of enforced racial segregation have been eliminated. The District Court noted that the effect of-. Emporia’s withdrawal would be a “substantial increase in the proportion of whites in the schools attended by city residents, and a concomitant decrease in the county schools.” 309 F. Supp., at 680. In addition, the court found that the departure of the city’s students, its leadership, and its financial support, together with the possible loss of teachers to the new system, would diminish the chances that transition to unitary schools in the county would prove “successful.”
Certainly, desegregation is, not achieved by splitting a single school system operating “white schools” and “Negro schools” into two new systems, each opérating unitary schools within its borders, where one of the two new systems is, in fact, “white” and the other is, in fact, “Negro.” Nor does a court supervising the process of desegregation exercise its remedial discretion responsibly where it approves a plan that, in the hope of providing better “quality education” to , some children, has a substantial adverse effect upon the quality of education available to others. In some cases, it may be readily perceived that a proposed subdivision of a school district will produce one or both of these results. In other cases, the likelihood of such results may be less apparent. ’ This case is of the latter kind, but an examination of the record shows that the District Court’s conclusions were adequately supported by the evidence. Data submitted lo the District Court at its December hearing showed that the school system in operation under the “pairing” plan, including both Emporia and the county, had a racial composition of 34% white and 66% Negro. If Emporia had established its own system, and if total enrollment had remained the same, the city's schools would have been 48% white and 52% Negro, while the county's schools would have been 28% white and 72% Negro.
We need not and do not hold that this disparity in the racial composition of the two systems would be a sufficient reason, standing alone, to enjoin the creation of the separate school district. The fact that a school board's desegregation plan leaves some disparity in racial balance among various schools in the system does not ' alone make that plan unacceptable. We observed in Swann,, supra, that “[t] he. constitutional command to desegregate schools does not mean that every school in every community must always reflect the racial composition of the.school system as a whole.” 402 U. S., at' 24.
But there is more to this case, than the disparity in racial percentages reflected by the figures supplied by the school board. In the first place, the District Court found that if Emporia were allowed to withdraw from the existing system, it “may be anticipated that the proportion of whites in- county schools may drop as those who can register in private academies,” 309 F. Supp., at 680, while some whites might return to the city schools from the private schools in which they had previously enrolled. Thus, in the judgment of the District Court, the statistical breakdown of the 1969-1970 enrollment figures between city residents and county residénts did not reflect what the situation would have been had Emporia established its own school system.
Sécond, the significance of any racial disparity in this case is enhanced by the fact that the two formerly all-white schools are located within Emporia, while all the schools located in the-surrounding county were formerly all-Negro. The record further reflects, that the school buildings in Emporia are better equipped and are located on better sites than are those in the county. We noted in Swann that factors such as these may in themselves indicate that enforced racial segregation has been perpetuated:
“Independent of student assignment, where it is possible to identify a ‘white ■ school’ or a ‘Negro school’ simply by reference to the racial composition of teachers and staff, the quality of school buildings and equipment, or the organization of sports activities, a prima facie case of violation of substantive constitutional rights under the Equal Protection Clause is shown.” 402 U. S., at 18.
Just as racial balance is not required. in remedying a dual system, neither are racial ratios the sole consideration to be taken into account in devising a workable remedy.
The timing of Emporia’s action is a third factor that was properly taken into account by the District Court in assessing the effect of the action upon children remaining in the county schools. While Emporia had long had the right under state law to establish a separate school system, its decision to do so came only upon the basis of — and, as the city officials conceded, in reaction to — a court order that prevented the county system from maintaining any longer the segregated system that had lingered for 15 years after Brown I. In the words of Judge Winter,, dissenting in the Court of Appeals, “[i]f the establishment of an Emporia school district is riot enjoined, the black students in the county will watch as nearly one-half the total number of white students in the county abandon the. county schools for a substantially whiter system.” 442 F. 2d, at 590; The message of this action, coming when it did, cannot have escaped the Negro children in the county. As we noted in Brown I: “To separate [Negro school children] from others of • similar age and qualifications solely because of their race generates a feeling of inferiority as to their status in the community that may affect their hearts and minds in a way unlikely ever to be undone.” 347 U. S., at 494. We think that, under the circumstances, the District Court could rationally have concluded that the same adverse psychological effect was likely to result from Emporia’s withdrawal Of .its children from the Greensville County system.
The weighing of these factors to determine their effect upon the process of desegregation is a delicate task that is aided by a. sensitivity to local conditions, and the judgment is primarily the responsibility of the district judge. See Brown II, supra, at 299. ' Given the totality of the circumstances, we hold that the District Court was justified in its conclusion that Emporia’s establishment of a separate system would actually impede the process of dismantling the existing dual system.
IV
Against these considerations,.Emporia advances arguments that a separate system is- necessary to achieve “quality education” - for city residents, and that it is unfair in any event to force the city to continue to send its children to schools over which the city, because of the character of its arrangement with the -county, has very little control. These arguments are entitled to consideration by a court exercising its equitable discretion where they are directed to the feasibility or practicality of the proposed remedy. See Swann v. Charlotte-Mecklenburg Board of Education, supra, at 31. But, as we said in .Green v. County School Board, supra, the availability of “more promising courses of action” to dismantle a dual system “at the least . . . places a heavy burden upon the board to explain its preference for an apparently less effective method.” 391 U. S., at 439.
In evaluating Emporia’s claims, it must be remembered that the city represents the interests of less than one-third of the students in the system being desegregated. Only the city officials argue that their plan is preferable to the “pairing” plan encompassing the whole of the city-county system. Although the county school board took no position in the District Court either for or against Emporia’s action, it had previously adopted a resolution stating its belief that the city’s action was not in the best interests of the county children.- In terms of Green, it was only the respondents — -not the county school board — who expressed a “preference for an apparently less effective method” of desegregation.
At the final hearing in the District Court, the respondents presented detailed budgetary proposals and other evidence demonstrating that they contemplated a more diverse and more expensive educational program than that to which the city children had been accustomed in the Greensville County schools. These plans for the city system were developed after the preliminary injunction was issued in this case. In'. August 1969, one month before classes were scheduled to open, the city officials were intent Upon operating a- separate system despite the fact that the city had no buildings under lease, no teachers under contract, and no specific plans for the operation of the schools. Thus, the persuasiveness of the “quality education”, rationale was open to question. More important, however, any increased quality of education provided to city students would, under the circumstances found by the District Court, have been purchased only at the price of a substantial adverse effect upon the viability of the county system. Tfye District Court, with its responsibility to provide an effective remedy for segregation in the entire cffy-county system, could not properly allow the city to make its part of that system more attractive where such a result would be accomplished at the expense of the children remaining in the county.
A moré weighty consideration put forth by Emporia is its lack of formal control over' the school system under the terms of its contract with the county. This argument is properly addressed to the practicality of the District Court’s action. As we said in Davis v. School Commissioners of Mobile County, 402 U. S., at 37:
“Having once found a violation, the- district judge or school authorities should make every effort to achieve the greatest possible degree of actual de- . segregation, taking into account the practicalities of the situation.”
And in Swann, supra, we noted that a desegregation plan cannot be regarded as a proper exercise of a district .court’s discretion where it is not “reasonable, fea- . sible and workable.” 402 U. S., at 31.
We do not underestimate the deficiencies, from Em-poria’s standpoint, in the arrangement by which it undertook in 1968 to provide for the education of its children. Direct control over decisions vitally affecting the education of one’s children- is a need that is strongly felt in our society, and since 1967 the citizens of Em-poria have hacl little of that control. But Emporia did find its'arrangement with the county both feasible and practical up until the time of the desegregation decree issued in the summer of 1969. While city officials testified that they were dissatisfied with the terms of the contract prior to that time, they did not attempt to change it. -They argued that the arrangement became intolerable when the “pairing” decree was entered, because the county officials who would control the budget of the unitary system lacked the desire to make the unitary system work. The District Court did not accept, the contention that a lack of enthusiasm on the part of county leaders would, if Emporia children, remained in the system, block a successful transition to unitary schools. The court felt that the “desire of the city leaders, coupled with their obvious leadership ability,” would make itself felt despite the absence, of any formal control by the city over the system’s budget and operation, and that the city’s leadership would be “an important facet in the successful operation of any court-ordered plan.” 309 F. Supp., at 679. Under these, circumstances, we cannot say that the enforced continuation of the single city-county system was not “reasonable, feasible and workable.”
The District Court explicitly noted in its opinion that its injunction does not have the effect of locking Em-poria into its present circumstances for all time. As already noted, oür holding today does not rest upon a conclusion that the disparity in racial balance between the city and county schools resulting from separate systems would, absent any other considerations, be unacceptable. The city’s creation of a separate school system was enjoined because of the effect it would have had at the time upon the' effectiveness of the remedy ordered to dismantle the dual system that had long existed in the area. Once the unitary system has been established and accepted, it may be that Emporia, if .it still desires to do so, may establish an independent system without such an adverse effect upon the students remaining in the county, or it may be able to work out a more satisfactory arrangement with the county for joint operation of the existing system. We hold only that a new school district may not be created where its effect would be to impede the process of dismantling a dual system. And in making that essentially factual determination in any particular case, “we must of necessity rely to a large extent, as this Court has for .more thán 16 years, on the informed judgment of the district courts in the first instance and on courts of appeals.” Swann, supra, at 28. In this case, we believe that the District Court did not. abuse its discretion. For these reasons, the judgment of the Court of Appeals is
Reversed.
Together with No. 70-187, Cotton v. Scotland Neck City Board of Education.
The companion cases were Davis v. Board of School Commissioners, 402 U. S. 33; McDaniel v. Barresi, 402 U. S. 39; Board of Education v. Swann, 402 U. S. 43; and Moore v. Board of Education, 402 U. S. 47.
On the same day that it reversed the District Court orders in ’ this case and in the Scotland Neck cases, the Court of Appeals for the Fourth Circuit affirmed an order enjoining the creation of a new school district in another county of North Carolina. Turner v. Littleton-Lake Gaston School District, 442 F. 2d 584. Other cases dealing with attempts to split school districts in the process of desegregation are Lee v. Macon County Board of Education, 448 F. 2d 746; Stout v. Jefferson County Board of Education, 448 F. 2d 403; Haney v. County Board of Education, 410 F. 2d 920; United States v. Texas, 321 F. Supp. 1043, 1052, aff'd, with modifications, 447 F. 2d 441; Burleson v. County Board of Election Commissioners, 308 F. Supp. 352, aff’d, 432 F. 2d 1356; Aytch v. Mitchell, 320 F. Supp. 1372.
Va. Code Ann. § 15.1-982.
See Va. Code Ann. §22-93; Colonial Heights v. County of Chesterfield, 196 Va. 155, 82 S. E. 2d 566 (1954).
Emporia was entitled under state law to establish an independent school system when it became a city in 1967. V ’ ’.it chose not to do so because, according to the testimony of the chairman of the city school board, a separate system did not seem practical at the time. In a letter to the County Board of Supervisors in July 1969, the Emporia City Council stated that it had authorized a combined system in 1968 because it believed that “the educational interest of Emporia citizens, their children and those of the citizens and children of Greensville County, could best be served by continuing a combined City-County school division, thus giving students from both political subdivisions full benefits of a larger school system.”
Under Virginia law as it stood in 1969, the school “division” was the basic unit for the purpose of school administration. See Va. Code Ann. §§ 22-30, 22-34, 22-100.1.
The plan was later modified in certain respects at the request of the county school board, and as modified it has been in operation since September 1969. Because the four schools located outside Emporia’s city limits are all-in close proximity to the city, the “pairing” plan apparently involved little- additional transportation of students.
The District Court took special note of . this transfer arrangement in its memorandum accompanying the preliminary injunction issued in August 1969. At the time of the final hearing, however, the respondents assured' the court that if allowed to operate a separate system, they would not permit transfers from the county without prior permission of the court.
Because the county school board had ultimate responsibility for the administration of the schools under the combined system, the members of the Emporia school board were not originally parties to the lawsuit. But the District Court’s desegregation decree bound both county officials “and their successors,” and the District Court treated the Emporia school board members, insofar as they intended to replace the county board as administrators of part of the system under court order, as “successors” to the members of the county board.
The decision of the Court of Appeals was rendered less than a month prior to our decision in Swann v. Charlotte-Mecklenburg Board of Education, 402 U. S. 1.
The court order that we approved in Swann, supra, itself provided for student bodies ranging from 9% Negro to 38% Negro.
“Full implementation, of these constitutional principles may require solution- of varied local school problems. School authorities have the primary responsibility for elucidating, assessing, and solving these problems; courts will have to consider whether the action of school authorities constitutes good faith implementation of the governing constitutional principles. Because of their proximity to local conditions and the possible need for further hearings, the courts which originally heard these cases can best perform this judicial appraisal.” 349 U. S., at 299.
City officials testified that one of the primary objections to the court’s “pairing” decree was that it required a student to attend six schools in the space of 12 years. Dr. Tracey, the expert witness for the respondents, expressed the view that this aspect of the decree had undesirable effects from an educator’s point of view. This argument, however, was never made to the District Court either before or at the time it adopted the “pairing” plan. Indeed, the city officials never even met with the county, school board or participated .in the hearings that' preceded the decree. After the June 25 order was entered, the District Court modified it at the request of the county board, and at the hearing on a preliminary injunction against Emporia’s withdrawal from the system, the court noted that it would be “delighted to entertain motions for amendment of the [pairing] plan at any time.” App. 185a.
The record shows that the pupil-teacher ratio in the county schools is less than 25 to' 1. Assuming some rough correspondence between this ratio and the size of classes, a 6% racial shift would represent a change in the racial identity of 1.5 students per class on the average.