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  <element name="DebtInstrumentRepaymentPremiumPercentage" id="hmhc_DebtInstrumentRepaymentPremiumPercentage" type="num:percentItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DebtInstrumentRepricingPeriod" id="hmhc_DebtInstrumentRepricingPeriod" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DebtInstrumentsFixedChargeCoverageRatio" id="hmhc_DebtInstrumentsFixedChargeCoverageRatio" type="xbrli:pureItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DebtInstrumentThirdPartyFeesAmount" id="hmhc_DebtInstrumentThirdPartyFeesAmount" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DeferredTaxAssetOperatingLossCarryforwardsAndOtherCarryforwards" id="hmhc_DeferredTaxAssetOperatingLossCarryforwardsAndOtherCarryforwards" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DeferredTaxAssetOperatingLossCarryforwardsAndOtherCarryforwardsDecrease" id="hmhc_DeferredTaxAssetOperatingLossCarryforwardsAndOtherCarryforwardsDecrease" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DeferredTaxAssetsDeferredIntercompanyInterest" id="hmhc_DeferredTaxAssetsDeferredIntercompanyInterest" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DeferredTaxAssetsDeferredIntercompanyInterestIncrease" id="hmhc_DeferredTaxAssetsDeferredIntercompanyInterestIncrease" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DeferredTaxAssetsGrossDeferredInterestDeductions" id="hmhc_DeferredTaxAssetsGrossDeferredInterestDeductions" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DeferredTaxAssetsMember" id="hmhc_DeferredTaxAssetsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DeferredTaxLiabilitiesDefiniteLivedIntangibleAssets" id="hmhc_DeferredTaxLiabilitiesDefiniteLivedIntangibleAssets" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DeferredTaxLiabilitiesDepreciationAndAmortization" id="hmhc_DeferredTaxLiabilitiesDepreciationAndAmortization" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DeferredTaxLiabilitiesIndefiniteLivedIntangibleAssets" id="hmhc_DeferredTaxLiabilitiesIndefiniteLivedIntangibleAssets" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DefinedBenefitPlanAmountsRecognizedInBalanceSheetTableTextBlock" id="hmhc_DefinedBenefitPlanAmountsRecognizedInBalanceSheetTableTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DefinedBenefitPlanForeignTerminationBenefits" id="hmhc_DefinedBenefitPlanForeignTerminationBenefits" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DefinedBenefitPlanQualifyingAge" id="hmhc_DefinedBenefitPlanQualifyingAge" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DefinedBenefitPlanServicePeriod" id="hmhc_DefinedBenefitPlanServicePeriod" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DefinedBenefitPlanSettlementCost" id="hmhc_DefinedBenefitPlanSettlementCost" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DefinedBenefitPlanUnfundedStatusOfPlan" id="hmhc_DefinedBenefitPlanUnfundedStatusOfPlan" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingBenefitObligationsTableTextBlock" id="hmhc_DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingBenefitObligationsTableTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="DocumentAndEntityInformationAbstract" id="hmhc_DocumentAndEntityInformationAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="EdtechMember" id="hmhc_EdtechMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="EducationalServicesMember" id="hmhc_EducationalServicesMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="EffectiveIncomeTaxRateReconciliationAccrualOfUncertainTaxPositions" id="hmhc_EffectiveIncomeTaxRateReconciliationAccrualOfUncertainTaxPositions" type="num:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="EffectiveIncomeTaxRateReconciliationAdjustmentPermanentItems" id="hmhc_EffectiveIncomeTaxRateReconciliationAdjustmentPermanentItems" type="num:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="EffectiveIncomeTaxRateReconciliationReleaseOfUncertainTaxPositionAdjustments" id="hmhc_EffectiveIncomeTaxRateReconciliationReleaseOfUncertainTaxPositionAdjustments" type="num:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="EmergingMarketsEquityMember" id="hmhc_EmergingMarketsEquityMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="EmployeeSeverancePolicyTextBlock" id="hmhc_EmployeeSeverancePolicyTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="EmployeesStockPurchasePlanMember" id="hmhc_EmployeesStockPurchasePlanMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="EmployeeStockPurchasePlanCompensationExpense" id="hmhc_EmployeeStockPurchasePlanCompensationExpense" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="EmployeeStockPurchasePlanPurchasePriceRange" id="hmhc_EmployeeStockPurchasePlanPurchasePriceRange" type="num:perShareItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="EquityMethodInvestmentsAndCostMethodInvestmentsAbstract" id="hmhc_EquityMethodInvestmentsAndCostMethodInvestmentsAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ExpenseRelatedToPriorYearMember" id="hmhc_ExpenseRelatedToPriorYearMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="FiniteLivedIntangibleAssetsAmortizedAtAnnualRateYearFive" id="hmhc_FiniteLivedIntangibleAssetsAmortizedAtAnnualRateYearFive" type="num:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="FiniteLivedIntangibleAssetsAmortizedAtAnnualRateYearFour" id="hmhc_FiniteLivedIntangibleAssetsAmortizedAtAnnualRateYearFour" type="num:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="FiniteLivedIntangibleAssetsAmortizedAtAnnualRateYearOne" id="hmhc_FiniteLivedIntangibleAssetsAmortizedAtAnnualRateYearOne" type="num:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="FiniteLivedIntangibleAssetsAmortizedAtAnnualRateYearThree" id="hmhc_FiniteLivedIntangibleAssetsAmortizedAtAnnualRateYearThree" type="num:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="FiniteLivedIntangibleAssetsAmortizedAtAnnualRateYearTwo" id="hmhc_FiniteLivedIntangibleAssetsAmortizedAtAnnualRateYearTwo" type="num:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="FirstQuarterTwoThousandAndFourteenMember" id="hmhc_FirstQuarterTwoThousandAndFourteenMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ForeignExchangeForwardContractMember" id="hmhc_ForeignExchangeForwardContractMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="FourthQuarterTwoThousandAndThirteenMember" id="hmhc_FourthQuarterTwoThousandAndThirteenMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="GoodwillAndOtherAssetsMember" id="hmhc_GoodwillAndOtherAssetsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="GovernmentBondsMember" id="hmhc_GovernmentBondsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="IncomeTaxBenefitExpenseMember" id="hmhc_IncomeTaxBenefitExpenseMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="IncomeTaxesLineItems" id="hmhc_IncomeTaxesLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="IncomeTaxesTable" id="hmhc_IncomeTaxesTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
  <element name="IncreaseDecreaseInNoncurrentDeferredTaxLiability" id="hmhc_IncreaseDecreaseInNoncurrentDeferredTaxLiability" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="IntangibleAssetsGrossIncludingGoodwill" id="hmhc_IntangibleAssetsGrossIncludingGoodwill" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="IntangibleLiabilityDisclosureAbstract" id="hmhc_IntangibleLiabilityDisclosureAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="InternationalFixedIncomeMember" id="hmhc_InternationalFixedIncomeMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="InternationalMember" id="hmhc_InternationalMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="InvestmentInPreferredStock" id="hmhc_InvestmentInPreferredStock" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="MeegeniusMember" id="hmhc_MeegeniusMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NewRevolvingCreditFacilityMember" id="hmhc_NewRevolvingCreditFacilityMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NonFinancialAssetsAbstract" id="hmhc_NonFinancialAssetsAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NonFinancialAssetsFairValueDisclosure" id="hmhc_NonFinancialAssetsFairValueDisclosure" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NonUsEquitySecuritiesMember" id="hmhc_NonUsEquitySecuritiesMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NumberOfClientsToWhomServicesAreProvided" id="hmhc_NumberOfClientsToWhomServicesAreProvided" type="xbrli:integerItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="NumberOfSubsidiariesAssetsIncludingStockAcquired" id="hmhc_NumberOfSubsidiariesAssetsIncludingStockAcquired" type="xbrli:integerItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="OperatingLeasesRentExpenseAdditionalRentals" id="hmhc_OperatingLeasesRentExpenseAdditionalRentals" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PaulsonAndCompanyIncMember" id="hmhc_PaulsonAndCompanyIncMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PaymentsForAdditionsToPrepublicationCost" id="hmhc_PaymentsForAdditionsToPrepublicationCost" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PensionPlansWithAccumulatedBenefitObligationInExcessOfPlanAssetsTableTextBlock" id="hmhc_PensionPlansWithAccumulatedBenefitObligationInExcessOfPlanAssetsTableTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PercentageOfCommonStockSharesIssuableUponExerciseOfWarrants" id="hmhc_PercentageOfCommonStockSharesIssuableUponExerciseOfWarrants" type="num:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PercentageOfOutstandingBorrowingCommitmentIssuedAsDiscount" id="hmhc_PercentageOfOutstandingBorrowingCommitmentIssuedAsDiscount" type="num:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PercentageOfTaxBenefitsRecognizedUponSettlement" id="hmhc_PercentageOfTaxBenefitsRecognizedUponSettlement" type="num:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PrePublicationCostsMember" id="hmhc_PrePublicationCostsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PrePublicationCostsNet" id="hmhc_PrePublicationCostsNet" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ProjectedBenefitObligationMember" id="hmhc_ProjectedBenefitObligationMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PropertyPlantAndEquipmentEstimatedLivesTableTextBlock" id="hmhc_PropertyPlantAndEquipmentEstimatedLivesTableTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PublishingRightsMember" id="hmhc_PublishingRightsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="PurchaseAccountingAdjustment" id="hmhc_PurchaseAccountingAdjustment" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="QuarterlyResultsOfOperationsLineItems" id="hmhc_QuarterlyResultsOfOperationsLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="QuarterlyResultsOfOperationsTable" id="hmhc_QuarterlyResultsOfOperationsTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
  <element name="RealEstateInvestmentsTrustMember" id="hmhc_RealEstateInvestmentsTrustMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ReductionInNetSaleMember" id="hmhc_ReductionInNetSaleMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="RegulatoryAssetsAbstract" id="hmhc_RegulatoryAssetsAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="RelatedPartyMember" id="hmhc_RelatedPartyMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="RemeasurementMember" id="hmhc_RemeasurementMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="RestructuringChargesAndAssociatedCost" id="hmhc_RestructuringChargesAndAssociatedCost" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="RoyaltiesMember" id="hmhc_RoyaltiesMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScheduleOfAccountsReceivableTable" id="hmhc_ScheduleOfAccountsReceivableTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
  <element name="ScheduleOfActuarialAssumptionsUsedToDetermineNetPeriodicBenefitCostTableTextBlock" id="hmhc_ScheduleOfActuarialAssumptionsUsedToDetermineNetPeriodicBenefitCostTableTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScheduleOfCarryingValuesAndEstimatedFairValuesOfDebtInstrumentsLineItems" id="hmhc_ScheduleOfCarryingValuesAndEstimatedFairValuesOfDebtInstrumentsLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScheduleOfCarryingValuesAndEstimatedFairValuesOfDebtInstrumentsTable" id="hmhc_ScheduleOfCarryingValuesAndEstimatedFairValuesOfDebtInstrumentsTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
  <element name="ScheduleOfComponentsOfIncomeLossBeforeIncomeTaxesLineItems" id="hmhc_ScheduleOfComponentsOfIncomeLossBeforeIncomeTaxesLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScheduleOfComponentsOfIncomeLossBeforeIncomeTaxesTable" id="hmhc_ScheduleOfComponentsOfIncomeLossBeforeIncomeTaxesTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
  <element name="ScheduleOfComponentsOfIncomeTaxExpenseBenefitByJurisdictionTableTextBlock" id="hmhc_ScheduleOfComponentsOfIncomeTaxExpenseBenefitByJurisdictionTableTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScheduleOfDeferredTaxAssetsAndLiabilitiesInBalanceSheetTableTextBlock" id="hmhc_ScheduleOfDeferredTaxAssetsAndLiabilitiesInBalanceSheetTableTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScheduleOfDefinedBenefitPlanAmountsThatWillBeAmortizedFromAccumulatedOtherComprehensiveIncomeExpenseInNextFiscalYearTableTextBlock" id="hmhc_ScheduleOfDefinedBenefitPlanAmountsThatWillBeAmortizedFromAccumulatedOtherComprehensiveIncomeExpenseInNextFiscalYearTableTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScheduleOfDefinedBenefitPlansActuarialAssumptionsUsedInCalculatingNetBenefitObligationsLineItems" id="hmhc_ScheduleOfDefinedBenefitPlansActuarialAssumptionsUsedInCalculatingNetBenefitObligationsLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScheduleOfDefinedBenefitPlansActuarialAssumptionsUsedInCalculatingNetBenefitObligationsTable" id="hmhc_ScheduleOfDefinedBenefitPlansActuarialAssumptionsUsedInCalculatingNetBenefitObligationsTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
  <element name="ScheduleOfFairValuesOfPensionPlanAssetsTableTextBlock" id="hmhc_ScheduleOfFairValuesOfPensionPlanAssetsTableTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScheduleOfValuationAndQualifyingAccountsTableTextBlock" id="hmhc_ScheduleOfValuationAndQualifyingAccountsTableTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ScholasticCorporationMember" id="hmhc_ScholasticCorporationMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SchoolChapterMember" id="hmhc_SchoolChapterMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SeasonalConcentrationRiskMember" id="hmhc_SeasonalConcentrationRiskMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SegmentAdjustedEbitda" id="hmhc_SegmentAdjustedEbitda" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ServicesProvidedOverNumberOfCountries" id="hmhc_ServicesProvidedOverNumberOfCountries" type="xbrli:integerItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SeveranceAndOtherChargesMember" id="hmhc_SeveranceAndOtherChargesMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="ShortTermInvestmentsMaturitiesDescription" id="hmhc_ShortTermInvestmentsMaturitiesDescription" type="xbrli:stringItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SignificantAccountingPoliciesLineItems" id="hmhc_SignificantAccountingPoliciesLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SignificantAccountingPoliciesTable" id="hmhc_SignificantAccountingPoliciesTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrldt:hypercubeItem"/>
  <element name="StockRepurchaseProgramAdditionalAuthorizedAmount" id="hmhc_StockRepurchaseProgramAdditionalAuthorizedAmount" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="StockRepurchaseProgramMember" id="hmhc_StockRepurchaseProgramMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="StockRepurchaseProgramNumberOfSharesRepurchasedDuringPeriod" id="hmhc_StockRepurchaseProgramNumberOfSharesRepurchasedDuringPeriod" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SubFacilityMember" id="hmhc_SubFacilityMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="SwinglineMember" id="hmhc_SwinglineMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="TermLoanMember" id="hmhc_TermLoanMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="TradePublishingMember" id="hmhc_TradePublishingMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="TransactionCostIncurredForThirdParties" id="hmhc_TransactionCostIncurredForThirdParties" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="TwoThousandFifteenOmnibusIncentivePlanMember" id="hmhc_TwoThousandFifteenOmnibusIncentivePlanMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="TwoThousandTwelveManagementIncentivePlanMember" id="hmhc_TwoThousandTwelveManagementIncentivePlanMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="UnrecognizedTaxBenefitsExcludingInterestAndPenalties" id="hmhc_UnrecognizedTaxBenefitsExcludingInterestAndPenalties" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitationsWithinNextTwelveMonths" id="hmhc_UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitationsWithinNextTwelveMonths" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="credit" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="UsEquityMember" id="hmhc_UsEquityMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="WarrantTerm" id="hmhc_WarrantTerm" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
  <element name="WeightedAverageCostOfCapital" id="hmhc_WeightedAverageCostOfCapital" type="num:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item"/>
</schema>


