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                                                                     EXHIBIT 2.1

                     PLAN OF REORGANIZATION AND ACQUISITION

                     PURSUANT TO SECTION 26B OF CHAPTER 172
                      OF THE GENERAL LAWS OF MASSACHUSETTS

     This Plan of Reorganization and Acquisition (the "Plan") is dated as of
March 12, 2001, and made between Lawrence Savings Bank, a Massachusetts savings
bank in stock form (the "Bank"), and LSB Corporation, a Massachusetts
corporation ("LSB Corp.").

     The Bank is a stock savings bank, duly organized and validly existing under
the laws of The Commonwealth of Massachusetts, with its principal office at 30
Massachusetts Avenue, North Andover, Massachusetts 01845. As of the date hereof,
the authorized capital stock of the Bank consists of (1) 20,000,000 shares of
common stock, par value $0.10 per share (the "Bank Common Stock"), of which
4,371,500 shares are issued and outstanding, 286,530 shares are reserved for
issuance under the Bank's 1986 Stock Option Plan (as the same may be renamed
from time to time), and, 158,800 shares are reserved for issuance under the
Bank's 1997 Stock Option Plan (the 1986 Stock Option Plan and the 1997 Stock
Option Plan are collectively referred to herein as the "Stock Option Plans"),
and (2) 5,000,000 shares of preferred stock, par value $0.10 per share, none of
which shares are issued and outstanding.

     LSB Corp. is a corporation, duly organized and validly existing under the
laws of The Commonwealth of Massachusetts, with its principal office at 30
Massachusetts Avenue, North Andover, Massachusetts 01845. The articles of
organization of LSB Corp. at the Effective Time (as defined herein) will provide
for authorized capital stock consisting of 20,000,000 shares of common stock,
par value $0.10 per share (the "LSB Corp. Common Stock"), and 5,000,000 shares
of preferred stock, par value $0.10 per share. As of the date hereof, there are
100 shares of LSB Corp. Common Stock issued and outstanding, all of which are
held by the Bank.

     The Bank and LSB Corp. have agreed that LSB Corp. will acquire all of the
issued and outstanding shares of Bank Common Stock (together with associated
preferred stock purchase rights) in exchange for shares of LSB Corp. Common
Stock (together with associated preferred stock purchase rights) pursuant to the
provisions of Section 26B of Chapter 172 of the General Laws of Massachusetts
and of this Plan. The Plan has been adopted and approved by a vote of a majority
of all the members of the Board of Directors of the Bank, and by a vote of a
majority of all the members of the Board of Directors of LSB Corp. The officers
of the Bank and of LSB Corp. whose respective signatures appear below have been
duly authorized to execute and deliver this Plan.

     Now, THEREFORE, in consideration of these premises, the Bank and LSB Corp.
agree as follows:

SECTION 1 -- APPROVAL AND FILING OF PLAN

     1.1. The Plan shall be submitted for approval by the holders of Bank Common
Stock at a meeting to be called and held in accordance with the applicable
provisions of law. Notice of such meeting shall be published at least once a
week for two successive weeks in a newspaper of general circulation in the
County of Essex, Commonwealth of Massachusetts. Both of said publications shall
be at least fifteen days prior to the date of the meeting.

     1.2. Upon approval of the Plan by the affirmative vote of the holders of 66
2/3% of the outstanding shares of Bank Common Stock as required by law, the Bank
and LSB Corp. shall submit the Plan to the Commissioner of Banks of The
Commonwealth of Massachusetts (the "Bank Commissioner") for his approval and
filing in accordance with the provisions of Section 26B of Chapter 172 of the
General Laws of Massachusetts. The Plan shall be accompanied by such
certificates of the respective officers of the Bank and LSB Corp. as may be
required by law and a written request from the Bank that the Plan not be filed
by the Bank Commissioner until such future time as the Bank Commissioner shall
have received from the


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Bank and LSB Corp. the written notice described in Subsection 2.1.

     1.3. If the requisite approval of the Plan is obtained at the meeting of
holders of Bank Common Stock referred to in Subsection 1.1, thereafter and until
the Effective Time, as hereinafter defined, the Bank shall issue certificates
for Bank Common Stock, whether upon transfer or otherwise, only if such
certificates bear a legend indicating that the Plan has been approved and that
shares of Bank Common Stock evidenced by such certificates are subject to
acquisition by LSB Corp. pursuant to the Plan.

SECTION 2 -- DEFINITION OF EFFECTIVE TIME

     2.1. The Plan shall become effective at 12:01 A.M. on the first business
day following the date on which the Bank and LSB Corp. advise the Bank
Commissioner in writing (i) that all the conditions precedent to the Plan
becoming effective specified in Section 5 have been satisfied and (ii) that the
Plan has not been abandoned by the Bank or LSB Corp. in accordance with the
provisions of Section 6, or at such other date and time as is specified in such
written notice to the Bank Commissioner. Such time is hereafter called the
"Effective Time."

SECTION 3 -- ACTIONS AT THE EFFECTIVE TIME

     3.1. At the Effective Time, LSB Corp. shall, without any further action on
its part or on the part of the holders of Bank Common Stock, automatically and
by operation of law acquire and become the owner for all purposes of all the
then issued and outstanding shares of Bank Common Stock (together with
associated preferred stock purchase rights) and shall be entitled to have issued
to it by the Bank a certificate or certificates representing such shares.
Thereafter, LSB Corp. shall have full and exclusive power to vote such shares of
Bank Common Stock, to receive dividends thereon and to exercise all rights of an
owner thereof.

     3.2. At the Effective Time, the shares of LSB Corp. Common Stock which are
outstanding immediately prior to the Effective Time shall be canceled.

     3.3. At the Effective Time, the holders of the then issued and outstanding
shares of Bank Common Stock (together with associated preferred stock purchase
rights) shall, without any further action on their part or on the part of LSB
Corp., automatically and by operation of law cease to own such shares and shall
instead become owners of one share of LSB Corp. Common Stock (together with
associated preferred stock purchase rights) for each share of Bank Common Stock
held by them immediately prior to the Effective Time. Thereafter, such persons
shall have full and exclusive power to vote such shares of LSB Corp. Common
Stock, to receive dividends thereon, except as otherwise provided herein, and to
exercise all rights of an owner thereof.

     3.4. At the Effective Time, all previously issued and outstanding
certificates representing shares of Bank Common Stock (the "Old Certificates")
shall automatically and by operation of law cease to represent shares of Bank
Common Stock or any interest therein and each Old Certificate shall instead
represent the ownership by the holder thereof of an equal number of shares of
LSB Corp. Common Stock. No holder of an Old Certificate shall be entitled to
vote the shares of Bank Common Stock formerly represented by such certificate,
or to receive dividends thereon, or to exercise any other rights of ownership in
respect thereof.

     3.5. Notwithstanding any of the foregoing, any Dissenting Stockholder, as
defined in Subsection 8.1, shall have such rights as are provided by Subsection
8.2 and by the laws of The Commonwealth of Massachusetts.

SECTION 4 -- ACTIONS AFTER THE EFFECTIVE TIME

     As soon as practicable and in any event not more than thirty days after the
Effective Time:

     4.1. LSB Corp. shall deliver to the transfer agent for the Bank and LSB
Corp. (the "Transfer Agent"),


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as agent for the then holders of the Old Certificates (other than Old
Certificates representing shares of Bank Common Stock as to which dissenters'
appraisal rights shall have been exercised), a certificate or certificates for
the aggregate number of shares of LSB Corp. Common Stock (the "New
Certificates"), to which said holders shall be entitled. Each such holder may
surrender his Old Certificate to the Transfer Agent and receive in exchange
therefor a New Certificate for an equal number of shares of LSB Corp. Common
Stock. However, holders of Old Certificates need not surrender Old Certificates
to the transfer Agent in exchange for a New Certificate. The Transfer Agent
shall treat Old Certificates as representing for all purposes an equal number of
shares of LSB Corp. Common Stock.

     4.2. LSB Corp. may publish a notice to the holders of all Old Certificates,
specifying the Effective Time of the Plan and notifying such holders that they
may present their Old Certificates to the Transfer Agent for exchange for a New
Certificate representing an equal number of shares of LSB Corp. Common Stock.
Such notice may likewise be given by mail to such holders at their addresses on
the Bank's records.

SECTION 5 -- CONDITIONS PRECEDENT

     The Plan and the acquisition provided for herein shall not become effective
unless all of the following first shall have occurred:

     5.1. The Plan shall have been approved by the affirmative vote of the
holders of two-thirds of the outstanding Bank Common Stock at a meeting of such
stockholders called for such purpose.

     5.2. The Plan shall have been approved by the Bank Commissioner and a copy
of the Plan with his approval endorsed thereon shall have been filed in his
office, all as provided in Section 26B of Chapter 172 of the General Laws of
Massachusetts.

     5.3. Any approval, consent, or waiver required by the Board of Governors of
the Federal Reserve System shall have been received, and any waiting period
imposed by applicable law shall have expired.

     5.4. The Bank shall have received a favorable opinion from KPMG, LLP,
satisfactory in form and substance to the Bank, with respect to the federal
income tax consequences of the Plan and the acquisition contemplated thereby.

     5.5. The shares of LSB Corp. Common Stock (together with associated
preferred stock purchase rights) to be issued to the holders of Bank Common
Stock pursuant to the Plan shall have been registered or qualified for such
issuance to the extent required under all applicable state securities laws.

     5.6. The Bank and LSB Corp. shall have obtained all other consents,
permissions and approvals and taken all actions required by law or agreement, or
deemed necessary by the Bank or LSB Corp., prior to the consummation of the
acquisition provided for by the Plan and to LSB Corp.'s having and exercising
all rights of ownership with respect to all of the outstanding shares of Bank
Common Stock acquired by it thereunder.

SECTION 6 -- ABANDONMENT OF PLAN

     6.1. The Plan may be abandoned by either the Bank or LSB Corp. at any time
before the Effective Time in the event that:

          (a) Necessary regulatory approvals cannot be obtained, or the
     conditions or obligations associated with such regulatory approvals make
     consummation of the acquisition contemplated by the Plan inadvisable in the
     opinion of Bank or LSB Corp.;

          (b) The number of shares of Bank Common Stock owned by Dissenting
     Stockholders, as defined in Subsection 8.1, shall make consummation of the
     acquisition contemplated by the Plan inadvisable in the opinion of the Bank
     or LSB Corp.;


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          (c) Any action, suit, proceeding or claim has been instituted, made or
     threatened relating to the Plan which shall make consummation of the
     acquisition contemplated by the Plan inadvisable in the opinion of the Bank
     or LSB Corp.; or

          (d) For any other reason consummation of the acquisition contemplated
     by the Plan is inadvisable in the opinion of the Bank or LSB Corp..

     Such abandonment shall be effected by written notice by either the Bank or
LSB Corp. to the other of them, and shall be authorized or approved by the Board
of Directors of the party giving such notice. Upon the giving of such notice,
the Plan shall be terminated and there shall be no liability hereunder or on
account of such on the part of the Bank or LSB Corp. or the Directors, officers,
employees, agents or stockholders of either of them. In the event of abandonment
of the Plan, the Bank shall pay the fees and expenses incurred by itself and LSB
Corp. in connection with the Plan and the proposed acquisition. If either party
hereto gives written notice of termination to the other party pursuant to this
section, the party giving such written notice shall simultaneously furnish a
copy thereof to the Bank Commissioner.

SECTION 7 -- AMENDMENT OF PLAN

     7.1. The Plan may be amended or modified at any time by mutual agreement of
the Boards of Directors of LSB Corp. and the Bank (i) prior to its approval by
the stockholders of the Bank, in any respect, and (ii) subsequent to such
approval, in any respect, provided that the Bank Commissioner shall approve of
such amendment or modification.

SECTION 8 -- RIGHTS OF DISSENTING STOCKHOLDERS

     8.1. "Dissenting Stockholders" shall mean those holders of Bank Common
Stock who file with the Bank before the taking of the vote on the Plan, written
objection to the Plan, pursuant to Section 86 of Chapter 156B of the General
Laws of Massachusetts, stating that they intend to demand payment for their
shares of Bank Common Stock if the Plan is consummated and whose shares are not
voted in favor of the Plan.

     8.2. Dissenting Stockholders who comply with the provisions of Sections 86
to 98, inclusive, of Chapter 156B of the General Laws of Massachusetts and all
other applicable provisions of law shall be entitled to receive from the Bank
payment of the fair value of their shares of Bank Common Stock upon surrender by
such holders of the certificates which previously represented shares of Bank
Common Stock. Certificates so obtained by the Bank, upon payment of the fair
value of such shares as provided by law, shall be canceled. Shares of LSB Corp.
Common Stock, to which Dissenting Stockholders would have been entitled had they
not dissented, shall be deemed to constitute authorized but unissued shares of
LSB Corp. Common Stock and may be sold or otherwise disposed of by LSB Corp. at
the discretion of, and on such terms as may be fixed by, its Board of Directors.

SECTION 9 -- STOCK OPTIONS; SHAREHOLDER RIGHTS PLAN

     9.1 By approving and entering into the Plan and by consummation of the
acquisition contemplated by the Plan, LSB Corp. shall have approved adoption by
LSB Corp. of the Stock Option Plans of the Bank as the Stock Option Plans of LSB
Corp. and shall have agreed to issue LSB Corp. Common Stock in lieu of Bank
Common Stock pursuant to stock options then outstanding under the Stock Option
Plans. As of the Effective Time, the unexercised portion of the options
outstanding under the existing Stock Option Plans shall be assumed by LSB Corp.
and thereafter shall be exercisable only for shares of LSB Corp. Common Stock,
with each such option being exercisable for a number of shares of LSB Corp.
Common Stock equal to the number of shares of Bank Common Stock that were
available thereunder immediately prior to the Effective Time, and with no change
in the exercise price or any other term or condition of such option. LSB Corp.
and the Bank shall make appropriate amendments to the Stock Option Plans to
reflect the adoption of such plans as the Stock Option Plans of LSB Corp.
without adverse effect upon the options outstanding


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under the Stock Option Plans.

     9.2 By approving and entering into the Plan and by consummation of the
acquisition contemplated by the Plan, and subject to any required third party
consents or approvals, LSB Corp. shall be deemed to have approved adoption by
LSB Corp. of the Rights Agreement dated as of December 19, 1996 between the Bank
and State Street Bank and Trust Company (the "Shareholder Rights Plan") as the
Shareholder Rights Plan of LSB Corp. and to have agreed to issue LSB Corp.
Preferred Stock in lieu of Bank Preferred Stock pursuant to preferred stock
purchase rights then outstanding under the Shareholder Rights Plan. As of the
Effective Time, the unexercised portion of the rights outstanding under the
existing Shareholder Rights Plan shall be assumed by LSB Corp. and thereafter
shall be exercisable only for shares of LSB Corp. Preferred Stock, with each
such right being exercisable for a number of shares of LSB Corp. Preferred Stock
equal to the number of shares of Bank Preferred Stock that were available
thereunder immediately prior to the Effective Time, and with no change in the
exercise price or any other term or condition of such right or Preferred Stock
except that any term or condition referring to the acquisition of a specified
number or percentage of outstanding shares of Bank Common or Preferred Stock
shall be deemed to refer respectively to a like number or percentage of
outstanding shares LSB Corp. Common or Preferred Stock. LSB Corp. and the Bank
shall make appropriate amendments to the Shareholder Rights Plan to reflect the
adoption of such plan as the Shareholder Rights Plan of LSB Corp. without
adverse effect upon any rights outstanding under the such plan.

SECTION 10 -- GOVERNING LAW

     The Plan shall take effect as a sealed instrument and shall be governed by
and construed in accordance with the laws of The Commonwealth of Massachusetts.


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SECTION 11 -- COUNTERPARTS

     The Plan may be executed in several identical counterparts, each of which
when executed and delivered by the parties hereto shall be an original, but all
of which together shall constitute a single instrument. In making proof of the
Plan, it shall not be necessary to produce or account for more than one such
counterpart.

                                               LAWRENCE SAVINGS BANK
BANK
                                               By: /s/ Paul A. Miller
                                                   ------------------------
                                                   Paul A. Miller
                                                   President and Chief
Executive Officer
ATTEST:

/s/ Robert P. Perreault
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Robert P. Perreault
Clerk

                                               LSB CORPORATION

                                               By: /s/ Paul A. Miller
                                                   --------------------------
                                                   Paul A. Miller
                                                   President and Chief
Executive Officer
ATTEST:

/s/ Robert P. Perreault
- --------------------------------
Robert P. Perreault
Clerk

     I hereby approve this Plan of Reorganization and Acquisition.

Date  6/22/01                                      /s/ Thomas J. Curry
                                                   ---------------------------
                                                   Thomas J. Curry
                                                   Commissioner of Banks


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