<?xml version="1.0" encoding="us-ascii"?><InstanceReport xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"><Version>2.4.0.8</Version><ReportLongName>0012 - Disclosure - CONVERTIBLE DEBT</ReportLongName><DisplayLabelColumn>true</DisplayLabelColumn><ShowElementNames>false</ShowElementNames><RoundingOption /><HasEmbeddedReports>false</HasEmbeddedReports><Columns><Column FlagID="0"><Id>1</Id><IsAbstractGroupTitle>false</IsAbstractGroupTitle><LabelSeparator>

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</LabelSeparator><Level>2</Level><ElementName>us-gaap_DebtDisclosureTextBlock</ElementName><ElementPrefix>us-gaap_</ElementPrefix><IsBaseElement>true</IsBaseElement><BalanceType>na</BalanceType><PeriodType>duration</PeriodType><IsReportTitle>false</IsReportTitle><IsSegmentTitle>false</IsSegmentTitle><IsCalendarTitle>false</IsCalendarTitle><IsEquityPrevioslyReportedAsRow>false</IsEquityPrevioslyReportedAsRow><IsEquityAdjustmentRow>false</IsEquityAdjustmentRow><IsBeginningBalance>false</IsBeginningBalance><IsEndingBalance>false</IsEndingBalance><IsReverseSign>false</IsReverseSign><FootnoteIndexer /><Cells><Cell FlagID="0" ContextID="From2012-09-01to2013-05-31" UnitID=""><Id>1</Id><IsNumeric>false</IsNumeric><IsRatio>false</IsRatio><DisplayZeroAsNone>false</DisplayZeroAsNone><NumericAmount>0</NumericAmount><RoundedNumericAmount>0</RoundedNumericAmount><NonNumbericText>&lt;p style="font: 10pt/normal Times New Roman, Times, Serif; margin: 0 15pt 0 0; text-align: justify"&gt;&lt;i&gt;NSC Investments&lt;/i&gt;&lt;/p&gt;

&lt;p style="font: 10pt/normal Times New Roman, Times, Serif; margin: 0; text-align: justify; text-indent: 0.5in"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 10pt/normal Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;In August 2008, we issued a promissory
note to NSC Investments Ltd. (&amp;#147;NSC&amp;#148;) in the principal amount of $250,000.&amp;#160;&amp;#160;Under the terms of this promissory
note (the &amp;#147;NSC 2008 Note&amp;#148;), interest is to be prepaid at the commencement of each quarter by us issuing 1,600 shares
of our common stock.&amp;#160;&amp;#160;The unpaid principal balance of the promissory note was due and payable in full on the sale of
any assets of the Company or November 1, 2008. Further consideration for the loan&amp;#160;&amp;#160;consisted of 15,000 shares of our
common stock at the funding, 5,000 shares of our common stock at the beginning of the next month, and 10,000 shares at the beginning
of the next month.&amp;#160;&amp;#160;This promissory note was extended until February 1, 2009. We agreed to pay 3,900 shares of our common
stock as interest and additional issuance of 10,000 shares of our common stock for additional compensation. The promissory note
was further extended to May 1, 2009 and we agreed to make payments on the principal of $50,000 by February 15, 2009; repay a further
$100,000 by May 1, 2009; issue 3,000 shares of our common stock as interest and additional issuance of 20,040 shares of our common
stock for additional compensation.&amp;#160;&amp;#160;All the terms of the amended agreement were complied with.&amp;#160;&amp;#160;The remaining
$100,000 plus accrued interest was convertible at NSC&amp;#146;s option at $2.00 per share on or before May 1, 2010. Pursuant to ASC
470-25-20, the modification of the Note agreement was not treated as an extinguishment but rather reduced the carrying amount of
the debt through an adjustment to the note discounts, with a corresponding increase in additional paid-in capital.&lt;/p&gt;

&lt;p style="font: 10pt/normal Times New Roman, Times, Serif; margin: 0; text-align: justify; text-indent: 0.5in"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 10pt/normal Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;In November 2010, the Company entered
into an agreement with NSC Investments Ltd. to issue 585,000 units (&amp;#147;Units&amp;#148;), at a price per Unit of $.20, each Unit
consisting of one share of common stock and a common stock purchase warrant to purchase one share of common stock at an exercise
price of $.30 per share, to settle the remaining balance of the $100,000 of principal debt and $17,500 of accrued interest.&amp;#160;&amp;#160;The
fair value of the warrants issued was $90,938.&lt;/p&gt;

&lt;p style="font: 10pt/normal Times New Roman, Times, Serif; margin: 0; text-align: justify; text-indent: 0.5in"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 10pt/normal Times New Roman, Times, Serif; margin: 0 0.25in 0 0; text-align: justify"&gt;&lt;font style="background-color: white"&gt;&lt;i&gt;2009
Convertible Debentures&lt;/i&gt;&lt;/font&gt;&lt;/p&gt;

&lt;p style="font: 10pt/normal Times New Roman, Times, Serif; margin: 0; text-align: justify; text-indent: 0.5in"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 10pt/normal Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;font style="background-color: white"&gt;On
January 15, 2009 we entered into an agreement with Genovese whereby Genovese and/or his affiliates (collectively &amp;#147;Genovese&amp;#148;)&amp;#160;&amp;#160;advanced
to the Company $250,000 for a convertible debenture or debentures (&amp;#147;the 2008 Genovese Convertible Debenture&amp;#148;) for the
aggregate principal amount of $250,000.&amp;#160;&amp;#160;The 2008 Genovese Convertible Debenture was non-interest bearing and matured
on December 5, 2010.&amp;#160;&amp;#160;At the holder&amp;#146;s sole discretion, the holder could elect to convert the 2008 Genovese Convertible
Debenture, in whole or in part into common shares of the Company at a conversion price of $0.10 per share.&amp;#160;&amp;#160;As additional
compensation, Genovese was issued a share purchase warrant certificate for 2,500,000 warrants, with each warrant exercisable into
one common share at $0.15 per share for a period of three years commencing from the date of the issuance of the warrant certificate.&amp;#160;&amp;#160;The
Company and Genovese further agreed to establish five (5) mutually agreed upon milestones to be attained no later than September
2009 with each milestone generally occurring approximately every forty five (45) days. In conjunction with the attainment of each
individual milestone, Genovese agreed to advance to the Company an additional $250,000. In connection with each $250,000 advance,
Genovese would be issued an additional $250,000 Debenture. The 2008 Genovese Convertible Debentures were non interest bearing and
mature two years from the date of issuance of each subsequent debenture (&amp;#147;2009 Convertible Debentures&amp;#148;).&lt;/font&gt; &lt;font style="background-color: white"&gt;At
the holders&amp;#146; sole discretion, the holder could elect to convert the 2009 Convertible Debentures, in whole or in part, at
any time prior to maturity, into common shares of the Company at a conversion price of $0.10 per share.&lt;/font&gt;&lt;/p&gt;

&lt;p style="font: 10pt/normal Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 10pt/normal Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;font style="background-color: white"&gt;As
additional compensation, Genovese was issued a share purchase warrant certificate for 2,500,000 warrants with each warrant exercisable
into one common share at $0.15 per share for a period of three years commencing from the date of the issuance of the warrant certificate
for each Convertible Debenture issued.&lt;/font&gt;&amp;#160;&amp;#160;The 2008 Genovese Convertible Debenture was subsequently amended for an
aggregate principal amount of $545,000. Additional 2008 Convertible Debentures for $455,000, $250,000, and $50,000 and $195,000
were issued during the year ended August 31, 2009.&amp;#160;&amp;#160;In April 2009, the amount of 2009 Convertible Debentures available
to be issued was increased by $255,000 for an aggregate of $1,750,000.&lt;/p&gt;

&lt;p style="font: 10pt/normal Times New Roman, Times, Serif; margin: 0; text-align: justify; text-indent: 0.5in"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 10pt/normal Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;As of August 31, 2009 a total of $1,750,000
principal amount of 2009 Convertible Debentures had been issued.&amp;#160;&amp;#160;The amount of the Debentures outstanding at August
31, 2009 was classified as &amp;#147;permanent equity&amp;#148; as capital in excess of par value and a corresponding amount was recorded
as a discount against the note payable.&amp;#160;&amp;#160;This discount was amortized over 24 months on a straight-line basis as interest
expense. On September 25, 2009, all issued 2009 Convertible Debentures were converted into 17,500,000 shares of common stock.&lt;/p&gt;

&lt;p style="font: 10pt/normal Times New Roman, Times, Serif; margin: 0; text-align: justify; text-indent: 0.5in"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 10pt/normal Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;&lt;i&gt;Janst Limited&lt;/i&gt;&lt;/p&gt;

&lt;p style="font: 10pt/normal Times New Roman, Times, Serif; margin: 0; text-align: justify; text-indent: 0.5in"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 10pt/normal Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;In April 2009, we entered into a loan
agreement with Janst Limited for $250,000.&amp;#160;&amp;#160;The terms of the loan were that the loan bears interest at 15% per annum,
matured on May1, 2010, and that the principal and accrued interest is convertible into common stock at the&amp;#160;&amp;#160;rate of $0.35
per share.&lt;/p&gt;

&lt;p style="font: 10pt/normal Times New Roman, Times, Serif; margin: 0; text-align: justify; text-indent: 0.5in"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 10pt/normal Times New Roman, Times, Serif; margin: 0; text-align: justify"&gt;In November 2010, the Company entered
into an agreement with Janst Limited to issue 1,515,625 units (&amp;#147;Units&amp;#148;), at a price per Unit of $.20, each Unit consisting
of one share of common stock and a common stock purchase warrant to purchase one share of common stock at an exercise price of
$.30 per share, to settle the $250,000 of principal debt and $53,125 of accrued interest.&amp;#160;&amp;#160;The fair value of the warrants
issued was $35,250. The fair value of the warrants was estimated using the Black-Scholes pricing method.&lt;/p&gt;</NonNumbericText><FootnoteIndexer /><CurrencyCode /><CurrencySymbol /><IsIndependantCurrency>false</IsIndependantCurrency><ShowCurrencySymbol>false</ShowCurrencySymbol><DisplayDateInUSFormat>false</DisplayDateInUSFormat></Cell></Cells><ElementDataType>nonnum:textBlockItemType</ElementDataType><SimpleDataType>na</SimpleDataType><ElementDefenition>The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.</ElementDefenition><ElementReferences>Reference 1: http://www.xbrl.org/2003/role/presentationRef

 -Publisher FASB

 -Name Accounting Standards Codification

 -Topic 505

 -SubTopic 10

 -Section 50

 -Paragraph 3

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

 -Publisher SEC

 -Name Regulation S-X (SX)

 -Number 210

 -Section 02

 -Paragraph 19, 20, 22

 -Article 5



Reference 3: http://www.xbrl.org/2003/role/presentationRef

 -Publisher FASB

 -Name Statement of Financial Accounting Standard (FAS)

 -Number 129

 -Paragraph 2, 4

 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.  This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.



Reference 4: http://www.xbrl.org/2003/role/presentationRef

 -Publisher FASB

 -Name Accounting Standards Codification

 -Topic 210

 -SubTopic 10

 -Section S99

 -Paragraph 1

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