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                                                                   Exhibit 10.21


                          SECOND SUPPLEMENTAL INDENTURE


         SECOND SUPPLEMENTAL INDENTURE, dated as of December 12, 1997, among
Atlantic Express Transportation Corp., a New York corporation (the "Company"),
the Guarantors named herein and The Bank of New York, a New York banking
corporation, as trustee (the "Trustee").

         WHEREAS, the Company has duly issued its 10 3/4% Senior Secured Notes
Due 2004 (the "Notes"), in the aggregate principal amount of $150,000,000
pursuant to an Indenture dated as of February 4, 1997, among the Company, the
Guarantors named therein and the Trustee, as amended by the First Supplemental
Indenture dated as of August 14, 1997, among the Company, the Guarantors named
therein and the Trustee (as amended, the "Indenture"), and the Notes are
outstanding on the date hereof; and

         WHEREAS, the Company has caused to be incorporated Atlantic-Chittenango
Real Property Corp., a New York corporation, Jersey Business Land Co., Inc., a
New Jersey corporation, and 201 West Sotello Realty, Inc., a California
corporation; and

         WHEREAS, Section 10.12 of the Indenture provides, among other things,
that the Company shall cause each Restricted Subsidiary that is formed or
acquired after the date of the Indenture to become a Guarantor thereunder and
execute and deliver a supplemental indenture pursuant to which such Restricted
Subsidiaries shall unconditionally guarantee all of the Company's Obligations as
set forth in Section 10.7 of the Indenture; and

         WHEREAS, Section 9.1 of the Indenture provides, among other things,
that the Company, the Guarantors and the Trustee may amend or supplement the
Indenture without the consent of any Holder to comply with Article 10.12 thereof
and execute a supplemental indenture; and

         WHEREAS, it is provided in Section 9.4 of the Indenture that a
supplemental indenture becomes effective in accordance with its terms and
thereafter binds every Holder; and

         NOW, THEREFORE, the parties hereto agree as follows:


SECTION 1  DEFINITIONS.

         Capitalized terms not defined herein shall have the meanings given to
such terms in the Indenture.




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SECTION 2  GUARANTEE BY RESTRICTED SUBSIDIARIES.

         Each of Atlantic-Chittenango Real Property Corp., Jersey Business Land
Co., Inc. and 201 West Sotello Realty, Inc. (collectively, the "Additional
Guarantors") unconditionally guarantees all of the Company's Obligations as set
forth in Section 10.7 of the Indenture in the same manner and to the same extent
as if it had executed the Indenture as one of the parties thereto defined as the
"Guarantors" therein.

SECTION 3  MISCELLANEOUS.

Section 3.1  Governing Law.

         THIS SECOND SUPPLEMENTAL INDENTURE SHALL BE CONSTRUED, INTERPRETED AND
THE RIGHTS OF THE PARTIES DETERMINED IN ACCORDANCE WITH THE LAWS OF THE STATE OF
NEW YORK, AS APPLIED TO CONTRACTS MADE AND PERFORMED WITHIN THE STATE OF NEW
YORK, WITHOUT REGARD TO PRINCIPLES OF CONFLICTS OF LAW. EACH OF THE ADDITIONAL
GUARANTORS HEREBY IRREVOCABLY SUBMITS TO THE JURISDICTION OF ANY NEW YORK STATE
COURT SITTING IN THE BOROUGH OF MANHATTAN IN THE CITY OF NEW YORK OR ANY FEDERAL
COURT SITTING IN THE BOROUGH OF MANHATTAN IN THE CITY OF NEW YORK IN RESPECT OR
ANY SUIT, ACTION OR PROCEEDING ARISING OUT OF OR RELATING OF ANY SUIT, ACTION OR
PROCEEDING ARISING OUT OF OR RELATING TO THIS AGREEMENT, AND IRREVOCABLY ACCEPTS
FOR ITSELF AND IN RESPECT OR ITS PROPERTY, GENERALLY AND UNCONDITIONALLY,
JURISDICTION OF THE AFORESAID COURTS. EACH OF THE ADDITIONAL GUARANTORS
IRREVOCABLY WAIVES, TO THE FULLEST EXTENT IT MAY EFFECTIVELY DO SO UNDER
APPLICABLE LAW, TRIAL BY JURY AND ANY OBJECTION THAT IT MAY NOW OR HEREAFTER
HAVE TO THE LAYING OF THE VENUE OF ANY SUCH SUIT, ACTION OR PROCEEDING BROUGHT
IN ANY SUCH COURT AND ANY CLAIM THAT ANY SUCH SUIT, ACTION OR PROCEEDING BROUGHT
IN ANY SUCH COURT HAS BEEN BROUGHT IN AN INCONVENIENT FORUM. EACH OF THE
ADDITIONAL GUARANTORS IRREVOCABLY CONSENTS, TO THE FULLEST EXTENT IT MAY
EFFECTIVELY DO SO UNDER APPLICABLE LAW, TO THE SERVICE OF PROCESS OF ANY OF THE
AFOREMENTIONED COURTS IN ANY SUCH ACTION OR PROCEEDING BY THE MAILING OF COPIES
THEREOF BY REGISTERED OR CERTIFIED MAIL, POSTAGE PREPAID, TO THE COMPANY AT ITS
ADDRESS SET FORTH IN THE INDENTURE, SUCH SERVICE TO BECOME EFFECTIVE 30 DAYS
AFTER SUCH MAILING. NOTHING HEREIN SHALL AFFECT THE RIGHT OF ANY PURCHASER TO
SERVE PROCESS IN ANY OTHER MANNER PERMITTED BY LAW OR TO COMMENCE LEGAL
PROCEEDINGS OR OTHERWISE PROCEED AGAINST EACH OF THE ADDITIONAL GUARANTORS IN
ANY OTHER JURISDICTION.


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Section 3.2  Continuing Agreement.

         Except as herein amended, all terms, provisions and conditions of the
Indenture, all Exhibits thereto and all documents executed in connection
therewith shall continue in full force and effect and shall remain enforceable
and binding in accordance with their terms.

Section 3.3  Conflicts.

         In the event of a conflict between the terms and conditions of the
Indenture and the terms and conditions of this Second Supplemental Indenture,
then the terms and conditions of this Second Supplemental Indenture shall
prevail.

Section 3.4  Counterpart Originals.

         The parties may sign any number of copies of this Second Supplemental
Indenture. Each signed copy shall be an original, but all of them together
represent the same agreement.

Section 3.5  Headings, etc.

         The Headings of the Sections of this Second Supplemental Indenture have
been inserted for convenience of reference only, are not to be considered a part
hereof and shall in no way modify or restrict any of the terms or provisions
hereof.


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<PAGE>



                                                      SIGNATURES

                  IN WITNESS WHEREOF, the parties hereto have executed and
delivered this Supplemental Indenture as of the date first written above.


                                                     ATLANTIC EXPRESS
                                                     TRANSPORTATION CORP.


                                                     By: /s/ Domenic Gatto
                                                         -----------------------
                                                            Name:  Domenic Gatto
                                                            Title: President

                                   GUARANTORS

<TABLE>

<S>                                       <C>   
BROOKFIELD TRANSIT INC.                   ATLANTIC PARATRANS, INC
AMBOY BUS CO., INC.                       180 JAMAICA CORP.
STATEN ISLAND BUS, INC.                   ATLANTIC EXPRESS COACHWAYS, INC.
RAYBERN CAPITAL CORP.                     ATLANTIC EXPRESS OF PENNSYLVANIA, INC.
METROPOLITAN ESCORT SERVICE, INC.         ATLANTIC PARATRANS OF KENTUCKY INC.
MERIT TRANSPORTATION CORP.                RAYBERN BUS SERVICE, INC.
TEMPORARY TRANSIT SERVICE, INC.             G.V.D. LEASING CO., INC.
ATLANTIC-HUDSON, INC.                     BLOCK 7932, INC.
COURTESY BUS CO., INC.                    ATLANTIC-CONN. TRANSIT, INC.
K. CORR, INC.                             ATLANTIC EXPRESS OF MISSOURI INC.
RAYBERN EQUITY CORP.                      ATLANTIC EXPRESS OF L.A. INC.
METRO AFFILIATES, INC.                    JERSEY BUS SALES, INC.
MIDWAY LEASING INC.                       JERSEY BUSINESS LAND CO. INC.
CENTRAL NEW YORK COACH                    201 WEST SOTELLO REALTY, INC.
    SALES & SERVICE, INC.
ATLANTIC-CHITTENANGO REAL
  PROPERTY CORP.
</TABLE>


                                          By: /s/ Domenic Gatto
                                              ---------------------------
                                                     Name:  Domenic Gatto
                                                     Title: President




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<PAGE>


                                       THE BANK OF NEW YORK, as Trustee


                                       By: /s/ Van K. Brown
                                           -------------------------
                                                 Name:  Van K. Brown
                                                 Title: Assistant Vice President


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