I am trying to connect mysql with CodeIgniter. I got this error:

load->database(); 
$query = $this->db->get('student'); return $query->result(); } } ?>

Fatal error: Class 'Student_model' not found in 
C:\wamp\www\CodeIgniter\system\core\Loader.php on line 303

Here is my code:

MODEL

class Student_model extends CI_Model
{

    function __Construct()

    {
        parent::__Construct();
    }

    public function student_getall()
    {
        $this->load->database();
        $query = $this->db->get('student');
        return $query->result();
    }
}

VIEW

foreach($query as $row)
{
    print $row->fname;
    print $row->lname;
    print $row->roll;
    print $row->address;
    print "
";
}

CONTROLLER

class Student extends CI_Controller
{
    function __Construct()
    {
        parent::__Construct();
    }

    public function getall()
    {
        $this->load->model('student_model');
        $data['query'] = $this->student_model->student_getall();
        $this->load->view('student_view',$data);
    }
}