﻿<?xml version="1.0" encoding="utf-8"?>
<Return xmlns="http://www.irs.gov/efile" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" returnVersion="2024v5.0">
  <ReturnHeader binaryAttachmentCnt="0">
    <ReturnTs>2025-01-23T09:47:29-05:00</ReturnTs>
    <TaxPeriodEndDt>2024-12-31</TaxPeriodEndDt>
    <PreparerFirmGrp>
      <PreparerFirmEIN>520891354</PreparerFirmEIN>
      <PreparerFirmName>
        <BusinessNameLine1Txt>ROBBINS ADAMS &amp; COMPANY</BusinessNameLine1Txt>
      </PreparerFirmName>
      <PreparerUSAddress>
        <AddressLine1Txt>126 MARKET SQ</AddressLine1Txt>
        <CityNm>CAMBRIDGE</CityNm>
        <StateAbbreviationCd>MD</StateAbbreviationCd>
        <ZIPCd>216131860</ZIPCd>
      </PreparerUSAddress>
    </PreparerFirmGrp>
    <ReturnTypeCd>990EZ</ReturnTypeCd>
    <TaxPeriodBeginDt>2024-01-01</TaxPeriodBeginDt>
    <Filer>
      <EIN>526000310</EIN>
      <BusinessName>
        <BusinessNameLine1Txt>CAMBRIDGE-SOUTH DORCHESTER HIGH</BusinessNameLine1Txt>
        <BusinessNameLine2Txt>SCHOOL MUSIC BOOSTERS INC</BusinessNameLine2Txt>
      </BusinessName>
      <BusinessNameControlTxt>CAMB</BusinessNameControlTxt>
      <PhoneNum>4102211089</PhoneNum>
      <USAddress>
        <AddressLine1Txt>5534 WHITEHALL ROAD</AddressLine1Txt>
        <CityNm>CAMBRIDGE</CityNm>
        <StateAbbreviationCd>MD</StateAbbreviationCd>
        <ZIPCd>21613</ZIPCd>
      </USAddress>
    </Filer>
    <BusinessOfficerGrp>
      <PersonNm>KIMBERLY BAIR</PersonNm>
      <PersonTitleTxt>TREASURER</PersonTitleTxt>
      <PhoneNum>4435212578</PhoneNum>
      <SignatureDt>2025-01-19</SignatureDt>
    </BusinessOfficerGrp>
    <IRSResponsiblePrtyInfoCurrInd>false</IRSResponsiblePrtyInfoCurrInd>
    <PreparerPersonGrp>
      <PreparerPersonNm>DAVID L THOMAS JR</PreparerPersonNm>
      <PTIN>P01221482</PTIN>
      <PhoneNum>4102280565</PhoneNum>
      <PreparationDt>2025-01-19</PreparationDt>
    </PreparerPersonGrp>
    <TaxYr>2024</TaxYr>
    <BuildTS>2024-10-15 13:58:12Z</BuildTS>
  </ReturnHeader>
  <ReturnData documentCnt="3">
    <IRS990EZ documentId="RetDoc1" referenceDocumentId="RetDoc2">
      <MethodOfAccountingCashInd>X</MethodOfAccountingCashInd>
      <ScheduleBNotRequiredInd>X</ScheduleBNotRequiredInd>
      <WebsiteAddressTxt>N/A</WebsiteAddressTxt>
      <Organization501c3Ind referenceDocumentId="RetDoc3">X</Organization501c3Ind>
      <TypeOfOrganizationCorpInd>X</TypeOfOrganizationCorpInd>
      <GrossReceiptsAmt>4</GrossReceiptsAmt>
      <InvestmentIncomeAmt>4</InvestmentIncomeAmt>
      <TotalRevenueAmt>4</TotalRevenueAmt>
      <FeesAndOtherPymtToIndCntrctAmt>450</FeesAndOtherPymtToIndCntrctAmt>
      <TotalExpensesAmt>450</TotalExpensesAmt>
      <ExcessOrDeficitForYearAmt>-446</ExcessOrDeficitForYearAmt>
      <NetAssetsOrFundBalancesBOYAmt>9332</NetAssetsOrFundBalancesBOYAmt>
      <NetAssetsOrFundBalancesEOYAmt>8886</NetAssetsOrFundBalancesEOYAmt>
      <CashSavingsAndInvestmentsGrp>
        <BOYAmt>9332</BOYAmt>
        <EOYAmt>8886</EOYAmt>
      </CashSavingsAndInvestmentsGrp>
      <Form990TotalAssetsGrp>
        <BOYAmt>9332</BOYAmt>
        <EOYAmt>8886</EOYAmt>
      </Form990TotalAssetsGrp>
      <NetAssetsOrFundBalancesGrp>
        <BOYAmt>9332</BOYAmt>
        <EOYAmt>8886</EOYAmt>
      </NetAssetsOrFundBalancesGrp>
      <InfoInScheduleOPartIIIInd>X</InfoInScheduleOPartIIIInd>
      <PrimaryExemptPurposeTxt>TO RAISE FUNDS AND ACCEPT DONATIONS TO BE USED FOR EDUCATIONAL PROGRAMS AND ACTIVITIES IN FUTHERANCE OF MUSIC AND BAND PROGRAMS SPONSORED BY CAMBRIDGE SOUTH DORCHESTER HIGH SCHOOL</PrimaryExemptPurposeTxt>
      <ProgramSrvcAccomplishmentGrp>
        <DescriptionProgramSrvcAccomTxt>MUSIC &amp; BAND SUPPLIES USED FOR THE EDUCATIONAL PURPOSES AND ACTIVITIES IN THE FUTHERANCE OF MUSIC AND BAND PROGRAMS SPONSORED BY CAMBRIDGE SOUTH DORCHESTER HIGH SCHOOL</DescriptionProgramSrvcAccomTxt>
        <ProgramServiceExpensesAmt>450</ProgramServiceExpensesAmt>
      </ProgramSrvcAccomplishmentGrp>
      <TotalProgramServiceExpensesAmt>450</TotalProgramServiceExpensesAmt>
      <OfficerDirectorTrusteeEmplGrp>
        <PersonNm>KIMBERLY BAIR</PersonNm>
        <TitleTxt>TREASURER</TitleTxt>
        <AverageHrsPerWkDevotedToPosRt>000.00</AverageHrsPerWkDevotedToPosRt>
        <CompensationAmt>0</CompensationAmt>
      </OfficerDirectorTrusteeEmplGrp>
      <OfficerDirectorTrusteeEmplGrp>
        <PersonNm>PEACHY SAN JUAN</PersonNm>
        <TitleTxt>SECRETARY</TitleTxt>
        <AverageHrsPerWkDevotedToPosRt>000.00</AverageHrsPerWkDevotedToPosRt>
        <CompensationAmt>0</CompensationAmt>
      </OfficerDirectorTrusteeEmplGrp>
      <OfficerDirectorTrusteeEmplGrp>
        <PersonNm>JESSICA SUGGS</PersonNm>
        <TitleTxt>PRESIDENT</TitleTxt>
        <AverageHrsPerWkDevotedToPosRt>000.00</AverageHrsPerWkDevotedToPosRt>
        <CompensationAmt>0</CompensationAmt>
      </OfficerDirectorTrusteeEmplGrp>
      <ActivitiesNotPreviouslyRptInd>false</ActivitiesNotPreviouslyRptInd>
      <ChgMadeToOrgnzngDocNotRptInd>false</ChgMadeToOrgnzngDocNotRptInd>
      <OrganizationHadUBIInd>false</OrganizationHadUBIInd>
      <SubjectToProxyTaxInd>false</SubjectToProxyTaxInd>
      <OrganizationDissolvedEtcInd>false</OrganizationDissolvedEtcInd>
      <Form1120PolFiledInd>false</Form1120PolFiledInd>
      <MadeLoansToFromOfficersInd>false</MadeLoansToFromOfficersInd>
      <EngagedInExcessBenefitTransInd>false</EngagedInExcessBenefitTransInd>
      <ProhibitedTaxShelterTransInd>false</ProhibitedTaxShelterTransInd>
      <BooksInCareOfDetail>
        <BusinessName>
          <BusinessNameLine1Txt>CSDHS MUSIC BOOSTERS INC</BusinessNameLine1Txt>
          <BusinessNameLine2Txt>CSDHS MUSIC BOOSTERS INC</BusinessNameLine2Txt>
        </BusinessName>
        <USAddress>
          <AddressLine1Txt>5534 WHITEHALL ROAD</AddressLine1Txt>
          <AddressLine2Txt>5534 WHITEHALL ROAD</AddressLine2Txt>
          <CityNm>CAMBRIDGE</CityNm>
          <StateAbbreviationCd>MD</StateAbbreviationCd>
          <ZIPCd>21613</ZIPCd>
        </USAddress>
        <PhoneNum>4102211089</PhoneNum>
      </BooksInCareOfDetail>
      <ForeignFinancialAccountInd>false</ForeignFinancialAccountInd>
      <ForeignOfficeInd>false</ForeignOfficeInd>
      <DonorAdvisedFndsInd>false</DonorAdvisedFndsInd>
      <OperateHospitalInd>false</OperateHospitalInd>
      <TanningServicesProvidedInd>false</TanningServicesProvidedInd>
      <RelatedOrganizationCtrlEntInd>false</RelatedOrganizationCtrlEntInd>
      <TransactionWithControlEntInd>false</TransactionWithControlEntInd>
      <PoliticalCampaignActyInd>false</PoliticalCampaignActyInd>
      <LobbyingActivitiesInd>false</LobbyingActivitiesInd>
      <SchoolOperatingInd>false</SchoolOperatingInd>
      <TrnsfrExmptNonChrtblRltdOrgInd>false</TrnsfrExmptNonChrtblRltdOrgInd>
      <PartVIOfCompOfHghstPdEmplTxt>NONE</PartVIOfCompOfHghstPdEmplTxt>
      <PartVIHghstPdCntrctProfSrvcTxt>NONE</PartVIHghstPdCntrctProfSrvcTxt>
      <FiledScheduleAInd>true</FiledScheduleAInd>
    </IRS990EZ>
    <IRS990ScheduleA documentId="RetDoc3">
      <PubliclySupportedOrg509a2Ind>X</PubliclySupportedOrg509a2Ind>
      <GiftsGrantsContrisRcvd509Grp>
        <CurrentTaxYearMinus4YearsAmt>650</CurrentTaxYearMinus4YearsAmt>
        <CurrentTaxYearMinus3YearsAmt>6430</CurrentTaxYearMinus3YearsAmt>
        <CurrentTaxYearMinus2YearsAmt>1515</CurrentTaxYearMinus2YearsAmt>
        <TotalAmt>8595</TotalAmt>
      </GiftsGrantsContrisRcvd509Grp>
      <GrossReceiptsAdmissionsGrp>
        <CurrentTaxYearMinus4YearsAmt>8</CurrentTaxYearMinus4YearsAmt>
        <CurrentTaxYearMinus3YearsAmt>6199</CurrentTaxYearMinus3YearsAmt>
        <CurrentTaxYearMinus2YearsAmt>7</CurrentTaxYearMinus2YearsAmt>
        <CurrentTaxYearMinus1YearAmt>634</CurrentTaxYearMinus1YearAmt>
        <CurrentTaxYearAmt>4</CurrentTaxYearAmt>
        <TotalAmt>6852</TotalAmt>
      </GrossReceiptsAdmissionsGrp>
      <GrossReceiptsNonUnrltBusGrp>
        <CurrentTaxYearMinus4YearsAmt>2002</CurrentTaxYearMinus4YearsAmt>
        <CurrentTaxYearMinus3YearsAmt>5194</CurrentTaxYearMinus3YearsAmt>
        <CurrentTaxYearMinus2YearsAmt>8093</CurrentTaxYearMinus2YearsAmt>
        <CurrentTaxYearMinus1YearAmt>2292</CurrentTaxYearMinus1YearAmt>
        <TotalAmt>17581</TotalAmt>
      </GrossReceiptsNonUnrltBusGrp>
      <Total509Grp>
        <CurrentTaxYearMinus4YearsAmt>2660</CurrentTaxYearMinus4YearsAmt>
        <CurrentTaxYearMinus3YearsAmt>17823</CurrentTaxYearMinus3YearsAmt>
        <CurrentTaxYearMinus2YearsAmt>9615</CurrentTaxYearMinus2YearsAmt>
        <CurrentTaxYearMinus1YearAmt>2926</CurrentTaxYearMinus1YearAmt>
        <CurrentTaxYearAmt>4</CurrentTaxYearAmt>
        <TotalAmt>33028</TotalAmt>
      </Total509Grp>
      <PublicSupportTotal509Amt>33028</PublicSupportTotal509Amt>
      <TotalSupportCalendarYearGrp>
        <CurrentTaxYearMinus4YearsAmt>2660</CurrentTaxYearMinus4YearsAmt>
        <CurrentTaxYearMinus3YearsAmt>17823</CurrentTaxYearMinus3YearsAmt>
        <CurrentTaxYearMinus2YearsAmt>9615</CurrentTaxYearMinus2YearsAmt>
        <CurrentTaxYearMinus1YearAmt>2926</CurrentTaxYearMinus1YearAmt>
        <CurrentTaxYearAmt>4</CurrentTaxYearAmt>
        <TotalAmt>33028</TotalAmt>
      </TotalSupportCalendarYearGrp>
      <PublicSupportCY509Pct>1.00000</PublicSupportCY509Pct>
      <PublicSupportPY509Pct>1.00000</PublicSupportPY509Pct>
      <InvestmentIncomeCYPct>0.00000</InvestmentIncomeCYPct>
      <InvestmentIncomePYPct>0.00000</InvestmentIncomePYPct>
      <ThirtyThrPctSuprtTestsCY509Ind>X</ThirtyThrPctSuprtTestsCY509Ind>
    </IRS990ScheduleA>
    <IRS990ScheduleO documentId="RetDoc2">
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>FORM 990-EZ, PART III</FormAndLineReferenceDesc>
        <ExplanationTxt>TO RAISE FUNDS AND ACCEPT DONATIONS TO BE USED FOR EDUCATIONAL PROGRAMS AND ACTIVITIES IN FUTHERANCE OF MUSIC AND BAND PROGRAMS SPONSORED BY CAMBRIDGE SOUTH DORCHESTER HIGH SCHOOL</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>FORM 990-EZ, PART III, LINE 28</FormAndLineReferenceDesc>
        <ExplanationTxt>MUSIC &amp; BAND SUPPLIES USED FOR THE EDUCATIONAL PURPOSES AND ACTIVITIES IN THE FUTHERANCE OF MUSIC AND BAND PROGRAMS SPONSORED BY CAMBRIDGE SOUTH DORCHESTER HIGH SCHOOL</ExplanationTxt>
      </SupplementalInformationDetail>
    </IRS990ScheduleO>
  </ReturnData>
</Return>