TAURO, C.J.

The plaintiff school committee seeks an order directing the defendant State board of education (board) to release certain State school aid withheld from its use under the provisions of the racial imbalance law. By way of counterclaim to the school committee's amended substitute bill for judicial review, the board prays that the school committee be ordered to adopt one of three racial balance plans, as per the board's decision of May 25, 1971, and that additional State school aid be ordered withheld pending compliance with the board's May 25th decision.

The case is here upon the reservation and report of a judge of the Superior Court under G.L.c. 214, § 31. See G.L.c. 213, § 1B, as amended by St. 1962, c. 722, § 4. The parties' statement of agreed facts, including 108 exhibits, may be summarized as follows.

Since October, 1965, the school committee has annually provided the board with statistics setting forth the percentage of nonwhite students in each public school under its supervision. The board determined, on the basis of the 1965 statistics, that racial imbalance existed in one junior high school and six elementary schools in Springfield. On April 1, 1966, to correct this imbalance, the school committee filed with the board a racial balance plan based on the recommendations of the board's own advisory committee (See G.L.c. 15, § 1K). This first plan provided, inter alia, for closing of one elementary school; alteration of school attendance districts; modification of the city's open enrollment program; and construction of one new elementary school and an addition to an existing junior high school. The board promptly approved the plan on April 12, 1966.

Statistics filed by the school committee in October, 1966, showed that, despite the short term measures taken under the first plan, there remained one imbalance, junior high school and five imbalanced elementary schools in the city. A second plan was then submitted to the board in July, 1967. The commissioner of education (commissioner), as executive head of the board, notified the school committee in a letter dated July 31, 1967, that the board regarded the plan as weak and it recommended certain changes in the plan. An impasse developed but was resolved with the submission of a revised second plan in September, 1967, which the board approved on October 24, 1967. The revised second plan contained the following elements: continuation of the modified open enrollment program; appointment of a director of school community relations; creation of a METCO program in the Springfield metropolitan area; further alteration of school attendance districts; phasing out of grades 5 and 6 at two elementary schools; and construction of three new elementary schools and an addition to one existing junior high school.

The October, 1967, statistical survey revealed continued imbalance at six schools in Springfield. Thereafter, on December 7, 1967, the board requested a detailed progress report on steps being taken to implement the second revised plan. The city's superintendent of schools responded on January 9, 1968, that only six white, and 171 nonwhite, students were participating in the open enrollment program and that, even with revised school attendance districts, the six schools remained racially imbalanced. No further action, however, was taken by the board until late 1968 when new annual statistics indicated that, despite the closing of the one imbalanced junior high school, racial imbalance continued to exist at five schools — all elementary. The board then required a new plan, and the school committee complied on March 17, 1969. The third plan, approved by the board on July 22, 1969, concluded as follows: "Racial balance can be maintained in all the new school complexes and in all new elementary schools of Springfield when the new facilities are available." In substance, the plan was similar to the revised second plan and, like that plan, placed greatest emphasis on school construction to achieve balance.

By October, 1969, the annual statistical census revealed that five schools still remained racially imbalanced, and on February 26, 1970, the board requested the school committee to submit an updated version of its third plan. The board further requested information concerning the effect of pupil transfers upon imbalance and any progress made toward the construction of new schools. The school committee provided this information in a letter dated April 1, 1970, but it did not submit an updated plan. On June 12, 1970, the commissioner notified the committee by letter that the board had unanimously passed the following resolution: "That the [s]chool [c]ommittee and . . . [its chairman] be put on notice immediately that their failure to comply with the racial imbalance law will result in . . . [the withholding of State school aid]." Notwithstanding the resolution, however, agents of the board (principally the assistant commissioner of education) held discussions with the school committee throughout the summer and fall of 1970, and at least with respect to the committee's proposed building program, the board encouraged the committee to proceed with its third plan, without revision.

The statistical survey made in October, 1970, as in the year before, showed that there were five racially imbalanced elementary schools. No indication was given by the board that a new or revised plan would be required, but on December 1, 1970, the commissioner wrote to the mayor of Springfield, as chairman of the school committee, that the board had requested a final recommendation on whether it should vote to withhold State school aid from Springfield. The commissioner further stated that his recommendation would depend, in part, upon information received regarding new school construction and on the implementation of short term measures. Upon receipt of the commissioner's letter, the mayor promptly forwarded to the commissioner copies of executed architectural contracts for all proposed school construction projects, and in a separate letter, he outlined the city's progress, as well as its problems, in trying to achieve racial balance.

The commissioner's response was a letter dated December 11, 1970, in which he stated as follows: "It appears from the information available to me that the [school construction] projects described in your letter will, upon their completion — and assuming that demographic factors remain relatively constant, eliminate racially imbalanced schools from the Springfield system. Therefore, although I have not considered . . . preferable long-range alternatives . . ., I believe that the [city's racial balance] plan complies with the requirements of the Act. . . . I note, however, that implementation of the plan remains contingent upon certain actions . . . [which must be] taken by you and the City Council."

The letter continued: "Consequently, I have concluded that, until all actions have been taken to make the system's commitment to its present long-range plan an unqualified one, the Springfield system will not have shown progress within a reasonable time in eliminating racial imbalance in its schools. For . . . [this] reason, . . . I will recommend to the [b]oard of [e]ducation that they instruct me to notify . . . [the appropriate State officials to defer payment of any school assistance to Springfield until] . . . the aforementioned contingencies have been fulfilled." In addition, the letter indicated: "My [second] recommendation will . . . [be] that . . . [, in any event, you must develop interim measures to eliminate racial imbalance by September, 1971, pending completion of all new schools, and if an acceptable proposal is not] received . . . by April 1, 1971, I shall feel constrained to advise the appropriate State officials at that time to defer any further payments of State monies."

At its December 15th meeting, the board voted a resolution adopting the commissioner's recommendations in full; however, no action was taken to withhold money from Springfield until January 4, 1971. The commissioner on that date certified the share of State School assistance due each city and town in the Commonwealth, but he placed the following notation next to Springfield's line: "Springfield not in compliance with the provisions of . . . [the racial imbalance law]; therefore, [the] State [b]oard of [e]ducation is withholding said funds until compliance." The amount thereby withheld was approximately 7.4 million dollars.

Subsequent to the board's vote, but before the commissioner's action, the commissioner received a letter dated December 26, 1970, from a representative of "People Take Action," a black community organization, in which the writer expressed opposition to the school construction aspect of Springfield's racial balance plan. The gist of the objection was that certain schools within the black community were to be phased out without any replacement, and as a consequence, black children would have to attend schools outside their community, thereby placing the burden of achieving racial balance primarily on blacks. To eliminate this feature of the plan, the letter recommended alteration of Springfield's building program, and it suggested that, without alteration, the plan might be subject to constitutional attack as violating the equal protection clause of the Fourteenth Amendment to the Constitution of the United States.

Within a few days of receipt of this letter, the commissioner wrote the mayor on December 31, 1970, as follows: "Since . . . [my last letter to you on December 11, 1970,] I have reviewed the transcripts of this . . . [department's hearing] in Springfield, and recent communications from citizens groups . . . that relate to the location of proposed schools. . . . [Upon consideration of these factors,] it is increasingly clear to me that, in the development of its long-range racial balance plan, your [s]chool [c]ommittee must operate fairly and equally, to the extent possible, on all segments of the affected community. . . . [A]ny inconvenience to pupils and parents . . . should be shared equitably by the entire community. Therefore . . . I now advise that you must incorporate the considerations to which I refer in any long-range planning."

Subsequent to this letter, and after State aid had been withheld, the Springfield city council on January 18, 1971, appropriated $150,000 toward the preparation of architectural drawings for the new schools contemplated by the city's racial balance plan. State aid, however, was not released, although the appropriation met the contingency set by the board in its December 15th vote. The commissioner in a letter dated January 20, 1971, acknowledged the city's action, but he reiterated his position of December 31, 1970: "[As I indicated previously,] this [d]epartment, on the basis of continuing legal developments, . . . questions whether your plans . . . satisfy present legal requirements. Therefore, . . . I must advise you again . . . that your present long-range range plan is not now acceptable." The commissioner noted further that the letter should not be construed as excusing the school committee from the requirement that an acceptable short-range proposal be submitted by April 1, 1971.

On January 26, 1971, in another letter on the subject, the commissioner indicated that the board had ratified his position and had reached certain additional "conclusions." These were that, while planning and constructions of one elementary school might continue, planning for the two other elementary schools should be discontinued pending a thorough review by a joint city-State task force. The reason given for "suspension" of planning was that the site of one school "would appear to burden [b]lack parents and children disproportionately" and that the site of a second school was also questionable on this score. The letter also indicated: "[P]lans that involve the building of new schools and the closing of existing ones should take into account the factors of convenience and fairness to the entire community . . . as well as factors of educational quality and the elimination of racial imbalance." Until such planning was undertaken, the commissioner stated, the school committee could not expect the release of State school assistance.

Notwithstanding this letter, on February 5, 1971, the commissioner and the school committee entered into a stipulation, whereby the commissioner withdrew notice of the city's noncompliance with the racial imbalance law. As a result, the funds withheld in January, 1971, were released to the city. It was also stipulated, however, that the release "in no way affects or prejudices the rights of either party in the case . . . [or] the [c]ommissioner's rights with respect to events which have occurred subsequent to December 15, 1970."

The commissioner wrote to the superintendent of schools on February 12, 1971, that it was his understanding that the stipulation had no effect on the April 1st deadline for submission of a short-range proposal. Subsequently, after consultations with the commissioner's staff, the city school department recommended that the school committee adopt any one of three short-term measures. The school department's report bears the date March 9, 1971.

The first option proposed was a "[c]luster [p]lan" involving the five imbalanced schools and seventeen other schools. There would be five clusters, each containing four or five schools, with students mixed between the schools in such a way as to achieve racial balance. The second option was "[g]rouping" involving fifteen schools, the five imbalanced schools and ten others. This method would require the matching of "each of the racially imbalanced schools with two schools which now have a relatively low percent of non-white pupils. Kindergarten through grade two . . . [would] be in one school, grades three and four in another school, and grades five and six in the third school." The third option was the "[p]airing" of each racially imbalanced school with another school. One school of each pair would have the primary grades (K to 3), and the other school, the intermediate grades (4 to 6). Each of the options would involve bussing of students, at a cost of $397,500 for the first option, $771,719 for the second option, and $449,240 for the third option.

On March 23, 1971, in anticipation that one of the options would be acceptable to the school committee, the board voted to extend the deadline for development of a short-range proposal from April 1 to May 18, 1971. However, on May 6, 1971, the school committee, by a four to three majority, refused to adopt any of the measures recommended by its staff. Subsequently, on May 25, 1971, the board voted the following resolutions: "[1.] The [b]oard of [e]ducation finds that the Springfield [s]chool [c]ommittee is not in compliance with the [b]oard's requirements of December 15, 1970. . . . The [b]oard reinvites the attention of the [s]chool [c]ommittee to the three plans developed by Springfield [s]chool [d]epartment . . . dated March 9, 1971. . . . [2.] [I]n view of the failure of the Springfield [s]chool [c]ommittee to comply with . . . [the racial imbalance law] the [c]ommissioner is directed to immediately notify . . . [the appropriate State officials to withhold State school assistance from the city.]"

In accordance with the board's vote, the commissioner immediately sent letters to the State comptroller and the State commissioner of corporations and taxation directing them to make no further disbursements from the money released under the stipulation of February 5, 1971, between the commissioner and the school committee. These funds remain in the State treasury pending a decision by this court.

1. It is well to note, as a preliminary matter, the nature of the issues before this court and the scope of today's decision.

By virtue of the racial imbalance law, it is the policy of this State "to encourage all school committees to adopt as educational objectives the promotion of racial balance and the correction of existing racial imbalance in the public schools." G.L.c. 71, § 37C. Compare 42 U.S.C. § 2000c (b), 2000c-6 (1970). The Supreme Court of the United States has emphasized the constitutional necessity of eliminating "all vestiges of state-imposed segregation." At the same time, however, it has also indicated that racial balance is not required by the Federal Constitution, although a State may, in its discretion, adopt a policy of achieving racial balance in its public schools. Swann v. Charlotte-Mecklenburg Bd. of Educ. 402 U.S. 1, 15-16. See United States v. Montgomery County Bd. of Educ. 395 U.S. 225, 236 (quoting from the brief submitted for the United States). See also School Comm. of Boston v. Board of Educ. 352 Mass. 693, 698, app. dism. 389 U.S. 572.

The principal issues which the parties have argued before this court concern the extent of the board's powers and jurisdiction under the racial imbalance law. Since there is no claim here that Springfield maintains a dual system of "racially separated school[s]" in violation of the mandate in Brown v. Board of Educ. of Topeka, 347 U.S. 483; S.C. 349 U.S. 294, our present concern is the interpretation and enforcement of the provisions of the Massachusetts racial imbalance act. Compare Swann v. Charlotte-Mecklenburg Bd. of Educ., supra, at 14. Although the issue of State imposed segregation is not before us on the present record, we believe that, if racial balance is the objective, our disposition of this case may lead to a plan which not only satisfies State law but also may eliminate any claim of unconstitutional racial discrimination in Springfield's public schools. See Barksdale v. Springfield Sch. Comm. 237 F. Supp. 543 (D. Mass.); S.C. sub nom. Springfield Sch. Comm. v. Barksdale, 348 F.2d 261 (1st Cir.).

2. With these preliminary observations, we turn now to the amended substitute bill for judicial review brought under G.L.c. 15, § 1J, first paragraph.

Initially, the commissioner withheld State school assistance from Springfield on the ground that the city had not demonstrated an "unqualified" commitment to implement its third racial balance plan. It appears from the record, however, that, on January 26, 1971, the board revoked its prior approval of the plan and authorized continued withholding of funds because of an alleged deficiency in the plan's building program.

While there is no express indication in G.L.c. 15, § 1I, that the board may revoke a previously approved plan, either in whole or in part, such authority is implied in appropriate circumstances because of the power to approve or disapprove plans. Moreover, it is significant that, under G.L.c. 71, § 37D, " [w]henever the state board of education finds that racial imbalance exists in a public school" (emphasis supplied), it must require submission of a plan which will correct the imbalance. On the basis of these provisions, we are satisfied that the board may, in appropriate circumstances, revoke a previously granted approval. Cf. Multi-Line Ins. Rating Bureau v. Commissioner of Ins. 357 Mass. 19, 22, and cases cited.

It is clear in the instant case that the circumstances were not appropriate for the exercise of this power. As the commissioner's letter of January 26, 1971, plainly states, the sole reason for the board's action was that, in achieving racial balance, the Springfield school building program might "burden [b]lack parents and children disproportionately." There is no evidence in the record which indicates that the city's program to construct new schools would operate in a discriminatory fashion. Where, as here, it is acknowledged that a plan meets all requirements of G.L.c. 71, § 37D, and it has not been established that a plan violates a constitutional guaranty, there is no basis for administrative action against the city. See G.L.c. 15, § 1I, first paragraph. While we recognize that compliance with the statute does not necessarily satisfy the constitutional guaranty of equal protection, it is fundamental in our system of government that courts, and not administrative agencies, must resolve conflicts which may arise between statutory and constitutional provisions. Massachusetts Constitution, Declaration of Rights, art. 30. See Panitz v. District of Columbia, 112 F.2d 39, 41-42 (D.C. Cir.); Davis, Administrative Law, § 20.04, p. 74. Cf. Bearce v. Zoning Bd. of Appeals of Brockton, 351 Mass. 316, 319-320.

Since the board was created by the Legislature (see G.L.c. 15, § 1E), it has "only the powers, duties and obligations expressly conferred upon it by . . . statute . . . or such as are reasonably necessary . . . [to carry out] the purpose for which it was established." Hathaway Bakeries, Inc. v. Labor Relations Commn. 316 Mass. 136, 141, and cases cited. In the instant case, if the board had doubts or was concerned about the constitutionality of the Springfield plan, its appropriate remedy was to seek declaratory relief under G.L.c. 231A. See G.L.c. 71, § 37D, seventh paragraph. See also School Comm. of Boston v. Board of Educ. 352 Mass. 693, 696-697; Wachusett Regional Sch. Dist. Comm. v. Erickson, 353 Mass. 77, 79-80. The board had no authority to take the action it did in the absence of a judicial declaration of a constitutional violation. In these circumstances, it was plainly error to continue withholding State school assistance past January 26, 1971.

Apart from this matter, the board argues that, in any event, after May 25, 1971, it had ample ground to withhold the city's share of State school funds because of the school committee's failure by that date to submit an acceptable short-term proposal.

Inasmuch as G.L.c. 71, § 37D, expressly mentions alteration of school attendance districts and transportation of pupils in connection with racial balance plans, there can be no doubt that a school committee under the section may utilize short-term as well as long-term methods of eliminating racial imbalance. See also G.L.c. 71, § 37C. While the language of c. 71, § 37D, further suggests that the Legislature meant to allow school committees a large measure of discretion in the selection of appropriate means, we think that the board also has responsibilities in this regard by virtue of G.L.c. 15 § 1I. Since this section and c. 71, § 37D, were enacted as part of the same bill, they should be construed together. See Platt v. Commonwealth, 256 Mass. 539 542; Marshal House, Inc. v. Rent Control Bd. of Brookline, 358 Mass. 686, 698-699. Pertinent here is the board's power under the second paragraph of c. 15, § 1I, to require a school committee to show "progress within a reasonable time in eliminating racial imbalance." A a necessary incident of this power, it would seem that, where a plan to correct imbalance involves construction of new schools over several years, the board must be able to require the city or town to formulate effective measures to deal with racial imbalance in the intervening period. Cf. Attorney Gen. v. Brissenden, 271 Mass. 172, 177-178.

In the instant case, by December, 1970, after five years under the racial imbalance law, the school committee had still not achieved racial balance in five elementary schools, although it had succeeded in eliminating imbalance in its junior high school system. It is uncontested that, without new interim measures, imbalance would have continued in the elementary school system until at least the 1973-1974 school year when the city expected to complete its building program. In these circumstances, it was clearly proper for the board on December 15, 1970, to direct the school committee to amend its third plan to ensure elimination of racial imbalance during the 1971-1972 school year.

While the board properly required the school committee to include new short-term measures in its plan, this step alone did not satisfy the board's responsibilities. Under G.L.c. 15, 1I, first paragraph, the board initially must "provide technical and other assistance in the formulation . . . of [racial balance] plans," and secondly, if a plan meeting the statutory requirements is not filed, the board must "consult with and make specific recommendations for a[n acceptable] plan by . . . [the] school committee." See the brief by the board at 7-8, filed in School Comm. of Boston v. Board of Educ. 352 Mass. 693. See also note, 5 Harv. J. Legis, 83, 90.

There is no dispute that the board met its first responsibility. This was accomplished in February and March, 1971, when the commissioner's staff assisted the city school department in the development of three short-term options for the school committee's consideration. The school committee contends, however, that the board did not fulfill its second responsibility of consultation and advice which arose in May, 1971, when the committee failed to file an acceptable plan. See G.L.c. 15, § 1I, first paragraph.

The facts support the committee's contention. There is nothing in the present record to indicate an offer of consultation by the board after the committee's failure to file a plan. Further, while it is true that the board did indicate it could accept any of the three optional proposals or a variation thereof, this action did not meet the requirement of "specific recommendations for a[n acceptable] plan." The Legislature must have had more in mind when it used both the word "specific" and the phrase "recommendations for a plan" in the first paragraph of G.L.c. 15, § 1I. See Republic Cas. Co. v. Scandinavian-American Bank, 2 F.2d 113, 114 (W.D. Wash.). See also Whittemore v. Town Clerk of Falmouth, 299 Mass. 64, 68-69. This view is borne out by the first paragraph of G.L.c. 15, § 1J, which provides that, upon judicial review, the court is to enforce the board's recommendations if they satisfy the requirements of the racial imbalance law. It can hardly have been intended, however, that the court should have to pick among several options, for this is not the function of a court in reviewing administrative action. It was clearly the intention of the Legislature that the board should make a single proposal in order to assist the school committee. An obvious concern of the Legislature in making this requirement was the important objective of facilitating the acceptance of a plan by the affected public.

For these reasons, we think that the board should have recommended just one proposal, and not three proposals and any number of possible variations. It is not intended that the board can now end the dispute and resolve all the attendant problems by recommending one of the three proposals. Other issues have now surfaced which require action as will appear later in this opinion (see points 3-5, infra).

If the board did not fulfil its own responsibilities under the first paragraph of G.L.c. 15, § 1I, it follows that it had no right under the second paragraph of the section to authorize the commissioner to withhold State school assistance. Aside from the case of a failure to make a reasonable progress toward the implementation of an approved plan, the language of the statute indicates only two instances where the commissioner may withhold State aid: (1) when a school committee rejects the board's specific recommendations for a plan; or (2) after specific recommendations have been made, the board rejects the school committee's revised plan. G.L.c. 15, § 1I, second paragraph, § 1J, first paragraph. In the instant case, since matters had not reached this stage, the board clearly exceeded its authority in directing the suspension of State school assistance.

For these reasons, we conclude that the monies withheld from Springfield should be released. Our action is meant in no way to relieve either party of the duty of eliminating racial imbalance in a timely fashion. We shall consider this matter further in connection with the board's counterclaim.

3. Before we deal with the counterclaim, it is appropriate to treat the school committee's request for an expression of our views as to the extent school attendance districts may be altered, and pupils transported, to eliminate racial imbalance. See G.L.c. 71, § 37D, second and fourth paragraphs. The issue has been argued by both parties and is clearly essential to the development of acceptable short-term measures. We express our views on the matter because judicial guidance may "expedite the disposition of this and possible future litigation." Goldblatt v. Corporation Counsel of Boston, 360 Mass. 660, 665. See Wellesley College v. Attorney Gen. 313 Mass. 722, 731.

The pertinent portion of the statute reads as follows: "[Every racial balance] plan shall, [inter alia], detail the changes in existing school attendance districts. . . . Any plan to detail changes in existing school attendance districts . . . with the intention of reducing or eliminating racial imbalance, must take into consideration on an equal basis with the above-mentioned intention, the safety of the children involved in travelling from home to school and school to home. . . .

" No school committee . . . shall be required as part of its plan to transport any pupil . . . to any school outside the school district established for his neighborhood, if the parent or guardian of such pupil files written objection thereto with such school committee" (emphasis supplied). G.L.c. 71, § 37D, second and fourth paragraphs.

We do not accept the school committee's contention that the emphasized language gives a parent the right to veto transportation of his child to any school which was not in his attendance district in 1965 when the statute was enacted. The words of the two quoted paragraphs, as a whole, clearly indicate a legislative intention to permit the alteration of district boundaries as a means of achieving racial balance. Construed in this light, the phrase "school district established for his neighborhood" means the attendance district which the school committee has chosen to establish for a pupil's neighborhood. See Industrial Technical Schs. Inc. v. Commissioner of Educ. 330 Mass. 622, 626. This would also seem to be the plain and ordinary meaning of the phrase. See Commonwealth v. Thomas, 359 Mass. 386, 387, and cases cited; G.L.c. 4, § 6, Third.

While the language is not open to the interpretation urged by the school committee, the restriction upon involuntary bussing must be read, at least to some degree, as placing a limitation upon redistricting as well as upon transportation policies. It is a firm rule of statutory construction that, in so far as the language used permits, every major provision of an enactment will be interpreted to make it an effectual part of the whole legislation. See Atlas Distrib. Co. v. Alcoholic Beverages Control Commn. 354 Mass. 408, 414. See also Insurance Rating Bd. v. Commissioner of Ins. 356 Mass. 184, 189, and cases cited. If, as the board urges, however, the statute does not limit the authority of school committees to redraw district boundaries, then the restriction upon involuntary bussing could be easily circumvented. Since the right to object to bussing arises only when a school committee proposes to transport a pupil outside his attendance district, it would be possible to nullify the restriction simply by establishing gerrymandered or excessively large districts.

We are convinced that the Legislature meant to forbid both practices. We reach this conclusion not only because allowing such districts would make a mockery of the provision concerning parental objections but also on the basis of the obligation imposed on school committees to establish school districts "for . . . neighborhood[s]" and to consider safety "on an equal basis" with racial balance.

Except where a particular word or phrase has a technical meaning, we interpret words and phrases in statutes in accordance with their common and approved usage. Canton v. Bruno, 361 Mass. 598, 607, n. 8. G.L.c. 4, § 6, Third. The word "neighborhood," as used in every day conversation, suggests a section of a city or town, identifiable as such by its history or geography, where people are generally known to each other or where they live in some proximity to each other. It will sometimes, but not always, be defined by natural or other physical boundaries or by an electoral or a zoning district. At the very least, however, the word signifies nearness, as opposed to remoteness, from home. See Langley v. Barnstead, 63 N.H. 246, 247.

While G.L.c. 71, § 37D, does not require attendance at the school "nearest to a pupil's neighborhood," it does clearly indicate by the phrase, "established for his neighborhood," that school attendance districts must bear a relationship to the neighborhood where the pupil and his family reside. This statutory mandate permits the drawing of fair and equitable, but enlarged, school attendance districts, and it does not preclude the use of such techniques as "pairing," "grouping," or "clustering" of schools when they achieve this result. We hold only that school attendance districts, when redrawn for the purpose of achieving racial balance, must bear a reasonable, though not necessarily a fixed, proximity to recognized neighborhoods. A school committee may, for example, include several neighborhoods and more than one school within an attendance district, but it must not draw district lines in such a way as to create a very large gerrymandered district. A more precise definition or guideline to cover every conceivable situation is not possible. Each case must be dealt with on the basis of its own facts. See Thomas v. Marshfield, 10 Pick. 364, 365, 367. See fns. 22, 23, and accompanying text, infra.

As to the second requirement that safety be given the same weight as achievement of racial balance, it has an obvious bearing upon the establishment of school attendance districts. While it is neither appropriate nor possible to detail every factor which bears upon the safety of school transportation, we may properly take this occasion to mention some of the most obvious factors: the distance to be travelled, the amount of time necessary for the journey, the availability of public transportation for pupils who wish to stay after school, the age of the children involved, and traffic hazards and the incidence of crime along the route. Since the racial imbalance existing in Springfield relates only to elementary schools, we observe that age may be an especially significant factor when transportation will involve young children. As a general rule, it would seem, the younger the pupil, the shorter the distance he may be required to travel consistent with the demands of safe transportation.

Subject to the limitations just described, school committees possess a large measure of discretion in the formulation of all aspects of racial balance plans, including alteration of school attendance districts and transportation of pupils. Under State law, such committees historically have exercised the functions of deciding which school attendance districts should be changed, which schools should be closed, and which schools should be used for other educational purposes. See Jantzen v. School Comm. of Chelmsford, 332 Mass. 175, 178, and cases cited. Had the Legislature intended a radical departure from this long established policy, we think it would have so indicated in clear language. See Leonard v. School Comm. of Springfield, 241 Mass. 325, 332; School Comm. of Gloucester v. Gloucester, 324 Mass. 209, 214; Dowd v. Dover, 334 Mass. 23, 26. A fair interpretation of G.L.c. 15, § 1I, based upon the statutory language as well as upon historical considerations, is that the board must accept a plan formulated at the local level if it reasonably appears to be designed to achieve racial balance and otherwise complies with the requirements of G.L.c. 71, § 37D.

Upon review of a local plan, the board, no less than the courts, is bound by the school committee's factual determinations, provided they are supported by substantial evidence. While the board must make its own independent determination whether a plan satisfies c. 71, § 37D, we suggest for the guidance of school committees that the board set forth beforehand how it interprets, and intends to apply, the requirements of the statute. The means of accomplishing this object are found in G.L.c. 30A, §§ 1 (2), (5), 2, 3, which establish rule-making procedures applicable to all but a few of the administrative agencies of State government. See also G.L.c. 30A, § 8 (advisory rulings). Although the usefulness of regulations should not be overrated, their importance is never greater than where, as here, an agency must interpret a legislative policy which is only broadly set out in the governing statute. See Cleary v. Cardullo's, Inc. 347 Mass. 337, 343-344. See also Environmental Defense Fund Inc. v. Ruckelshaus, 439 F.2d 584, 596-598 (D.C. Cir.).

4. We consider next the board's counterclaim invoking the general equitable jurisdiction of this court.

With respect to short term measures, we are not prepared at this time to say that the school committee should be ordered to include in its plan any of the three options prepared by the city school department with the assistance of the board. Such an order is plainly inappropriate before the board has consulted with, and made specific recommendations to, the school committee for a single, acceptable short-term program. See G.L.c. 15, § 1I, first paragraph. See also notes, 46 B.U.L. Rev. 45, 66; 5 Harv. J. Legis, 83, 91.

Moreover, it has not been shown on the record before us that any of the options takes safety into account on an equal basis with racial balance, or that school attendance districts, as redrawn, will bear a reasonable relationship to existing neighborhoods. See G.L.c. 71, § 37D, second and fourth paragraphs. While it is possible that one or more of the options meet these requirements, the record before us is inadequate to permit a ruling on this issue. Even where specific recommendations have been made, the courts are without power to order a school committee to adopt the recommended measures unless the evidence is sufficient to establish that the measures satisfy all statutory requirements of G.L.c. 71, § 37D. See G.L.c. 15, § 1J, first paragraph.

For these reasons, it is not appropriate to grant the first prayer of the counterclaim for an order directing the school committee forthwith to implement one of the three proposed, short-term programs. As to the second prayer, there is no basis for withholding State school assistance from Springfield, at least until such time as the school committee has had an opportunity to act upon specific recommendations by the board.

Nothing we have said should be construed as an indication of our approval of the school committee's performance in complying with the racial imbalance law. Although we are not prepared to say that the performance of the school committee — or perhaps lack of performance — permits the board to withhold State funds, and while we do not order the specific relief requested, the board is entitled to some relief under our general equity jurisdiction, which it seeks to invoke by its counterclaim. See G.L.c. 71, § 37D, seventh paragraph; c. 214, §§ 1, 2. See also Commissioner of Banks v. Commonwealth-Atlantic Natl. Bank, 248 Mass. 302, 306-307.

Inasmuch as Springfield has failed to achieve racial balance in its elementary school system in the period since 1965, we think it is reasonable to require that the school committee, with appropriate assistance from the board, develop short-term measures consistent with G.L.c. 71, § 37D, which will achieve racial balance in all city schools by September, 1973. With this end in view (see G.L.c. 71, § 37C), we remand the counterclaim to the Superior Court with directions that, after hearing the parties, the court establish a schedule for the submission of specific recommendations by the board, for the filing of a short-term program by the school committee, and for final action by the board, with sufficient time to allow for judicial review if required.

5. Since the board apparently entertains constitutional doubts with respect to Springfield's long range program to build new schools, it may seek to amend its counterclaim in the Superior Court to include a prayer for declaratory relief on this question. G.L.c. 71, § 37D, seventh paragraph; c. 231A. If the board so moves to amend its counterclaim the motion should be allowed. See G.L.c. 231, § 51. See also Reading v. Attorney General, ante, 266, 271.

While we will sometimes express an opinion on an issue not necessary to adjudicate the claim immediately before us (see Wellesley College v. Attorney Gen. 313 Mass. 722, 731), we cannot decide a constitutional question unless it is properly presented. In this respect, we have said: "Only when the impact of a statute upon particular individuals . . . and upon a set of definite facts . . . has been shown, can a court decide a constitutional question with confidence that relevant considerations have not been overlooked." Bowe v. Secretary of the Commonwealth, 320 Mass. 230, 246. What is lacking in the present record (see fn. 13, supra), are facts which would permit us to determine whether the proposed new school sites, approved in accordance with State law, will have the effect of depriving black parents and children of the equal protection of the laws. United States Constitution, Fourteenth Amendment. Massachusetts Constitution, Declaration of Rights, art. 1. It is for that reason that we express no opinion on the constitutional issue at the present time. Compare Commonwealth v. Gilfedder, 321 Mass. 335, 337-338.

In the Superior Court, however, upon a prayer for a declaratory decree, the parties will have the opportunity, not possible here, for a full evidentiary hearing where they can develop a record which is adequate for constitutional adjudication. See Pinnick v. Cleary, 360 Mass. 1, 37-38 (concurring opinion). Among other things, the judge should receive in evidence the most recent information concerning the impact of Springfield's proposed school building program. This should include the so called "Clinchy Report," which is not in the present record, but which the parties have informed us may have a material bearing on this case.

If the judge, after hearing the parties, decides to reserve and report the constitutional question for the consideration of this court, he should provide us not only with all evidence presented by the parties but also with appropriate findings and rulings. Since cases coming to us under G.L.c. 214, § 31, must be "ready for a final judgment" ( Taft v. Stoddard, 141 Mass. 150), as a general matter it is essential to have such findings and rulings before us especially where the evidence is either complex or conflicting. See M. Steinert Sons Co. v. Tagen, 207 Mass. 394, 397; Daly v. Foss, 209 Mass. 470, 471. In the event a statement of agreed facts is offered by the parties, the judge should make certain that the statement contains all facts, pertinent to each issue reserved and reported, and necessary for a final decree in the case. Cf. Whitney v. Wellesley Boston St. Ry. 197 Mass. 495, 502.

Regardless of any legal problems concerning Springfield's long-range program to build new schools, the judge below must insist on development and implementation of effective short-term measures by September, 1973. In remanding the counterclaim to the Superior Court with these instructions, we are not unmindful that the school committee's reluctance in May, 1971, to adopt a short-term program may have been based in large measure upon the board's abrupt turnabout in policy between December 15, 1970, and January 26, 1971, toward the long-range, building program. Therefore, although it is not possible at this time to set a date certain for the construction of new schools, we expect that the board will move expeditiously to resolve its doubts concerning the long-range program so that Springfield will have the new schools which it is authorized to build under the racial imbalance law. See G.L.c. 15, § 1I, third paragraph.

6. We think it appropriate to remind the parties that, under the racial imbalance law, the duty of correcting imbalance in the public schools is primarily upon State and local educational authorities, and not upon the courts. In the first instance, each local school committee must devise a racial balance plan, and if the committee fails to accomplish the legislative objective then State authorities must recommend a satisfactory plan. While we recognize that these tasks may be unpleasant and controversial as well as difficult to perform, the agencies concerned should understand that the assistance which courts can offer is limited both by the racial imbalance law itself and by the State Constitution. See G.L.c. 15, § 1J; c. 71, § 37D, seventh paragraph; Massachusetts Constitution, Declaration of Rights, art. 30. Thus, although we will pass on questions of law related to the interpretation and the enforcement of the statute, it is not appropriate for us to enter directly into the formulation of racial balance plans, for this is a strictly administrative function committed to agencies of the executive department of government. See Berman v. Board of Registration in Medicine, 355 Mass. 358, 360. See also fns. 22, 23, and accompanying text, supra.

7. On the school committee's bill, a final decree is to be entered setting aside the orders of January 4, and May 25, 1971, withholding State school assistance from Springfield. On the counterclaim, an interlocutory decree is to be entered remanding the case to the Superior Court for further proceedings in accordance with this opinion.

So ordered.