ASP.NET mvc : populate data (bind data) in two listboxes [duplicate]

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ASP.NET mvc : populate (bind data) in listbox

this is what I have: I have a database with a table named "Students". I also have a partial class "Students". I need to show to listboxes to the users: one with normal students and one with students who haven't got a class. So I have one actionresult returning two listboxes... but it's not working... what do I do wrong?

This is the layout of the partial class "Docent":

public IEnumerable<Student> GiveStudentsNormal(int lesson, int klass)
        {
            Lesson l = giveLesson(lesson);
            Klass k = GiveKlass(lesson, klass);
            return (k.Students).AsEnumerable();
        }


public IEnumerable<Student> GiveStudentsNoClass(int lesson, int klass)
            {
                Lesson l = giveLesson(lesson);
                Klass k = GiveKlass(lesson, klass);
                return (k.Students).AsEnumerable();
            }

So in my controller I use those students lists to populate my two listboxes. So one controller needs to populate those two lisboxes who are in the same view. But my question is, can I pass the object "Student" to my listbox? Or should I convert everything to strings?

Class StudentModel:

public class StudentModel
    {
        public IEnumerable<String> NormalStudents { get; set; }
        public IEnumerable<String> NoClassStudents { get; set; }
    }

But do I need the class StudentModel actually? Controller:

public ActionResult IndexStudents(Docent docent, int lessonid, int klassid)
        {
            var studentModel = new StudentModel
            {
               NormalStudents = docent.GiveStudentsNormal(lessonid, classid),
               NoClassStudents = docent.GiveStudentsNoClass(lessonid, classid)
            };

            return View(studentModel);
        }

View:

<asp:Content ID="Content2" ContentPlaceHolderID="MainContent" runat="server">

    <h2>IndexStudents</h2>
    <div class="editor-field">
    <%: Html.ListBox("IndexStudentsNormal", Model.NormalStudents) %>
  </div>

  <div class="editor-field">
    <%: Html.ListBox("IndexStudentsNoClass", Model.NoClassStudents) %>
  </div>

</asp:Content>

The view also returns an error: it doesn't know the methods NormalStudents and NoClassStudents

What do I have to do?