xml schema validation, please help I am student that is stuck!

<?xml version="1.0"?>

<xsd:schema xmlns:xsd= "http://www.w3.org/2001/XMLSchema">

<xsd:element name="libray" type="libray"/>
<xsd:complexType name="libray">
<xsd:sequence>
<xsd:element name="item" type="xsd:integer"
maxOccurs="unbounded"/>
</xsd:sequence>
</xsd:complexType>

<xsd:complexType name="item">
<xsd:sequence>
<xsd:element name="number" type="xsd:integer"/>
<xsd:element name="material" type="xsd:string"/>
<xsd:element name="name" type="xsd:string"/>
<xsd:element name="title" type="xsd:string"/>
<xsd:element name="publisher" type="xsd:string"/>
<xsd:element name="place" type="xsd:string"/>
<xsd:element name="date" type="xsd:date"/>
<xsd:element name="pagination" type="xsd:integer"/>
<xsd:element name="description" type="xsd:string" minOccurs="0"/>
<xsd:element name="isbn" type="xsd:integer" minOccurs="0"/>
</xsd:sequence>
</xsd:complexType>


<xsd:element name="item2"/>
<xsd:complexType name="item2">
<xsd:sequence>
<xsd:element ref="number"/>
<xsd:element ref="material"/>
<xsd:element ref="name"/>
<xsd:element ref="title"/>
<xsd:element ref="publisher"/>
<xsd:element ref="place"/>
<xsd:element ref="date"/>
<xsd:element ref="pagination"/>
<xsd:element ref="description"/>
<xsd:element ref="isbn"/>
</xsd:sequence>
</xsd:complexType>
</xsd:schema>
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<?xml version="1.0"?>
<myLibrary>
<item>
<number>96050228</number>
<material>Book (Print, Micro form, Electronic, etc.)</material>
<name>McCourt, Frank</name>
<title>Angela's ashes : a memoir</title>
<publisher>Wheeler Publisher</publisher>
<place>Rockland, MA</place>
<date>1997</date>
<pagination>517 p.</pagination>
<description>24 cm.</description>
<isbn>1568953968</isbn>
</item>
<item>
<number>99025057</number>
<material>Book (Print, Micro form, Electronic, etc.)</material>
<name>Castillo, Ana</name>
<title>Peel my love like an onion</title>
<publisher>Doubleday</publisher>
<place>New York</place>
<date>1999</date>
<pagination>213 p.</pagination>
<description>22 cm.</description>
<isbn>0385496761</isbn>
</item>
<item>
<number>2004577077</number>
<material>Compact Disc Music Sound Recording</material>
<name>Urban, Keith</name>
<title>Somebody like you</title>
<company>Capitol Records</company>
<place>United States</place>
<year>2002</year>
<description>4 3/4 in</description>
</item>
<item>
<number>2004591490</number>
<material>Compact Disc Music Sound Recording</material>
<name>Urban, Keith</name>
<title>Be here </title>
<company>Capitol Records</company>
<place>Nashville, TN</place>
<year>200</year>
<description>4 3/4 in</description>
</item>
</myLibrary>