Class School
{
public string studentname;
public string studentID
public string roomname;
public string roomID
}

Class School
    {
    public Student x;
    public Room y
    }
class Student
{
 public string studentname;
    public string studentID
}
class Room
{
    public string roomname;
    public string roomID
}

<School>
     <studentname>xxx</studentname>
     <studentID>yyy</studentID>
     <roomname>zzz</roomname>
     <roomID>ddd</roomID>
</School>