custom adapter with Checkbox

I`m trying to delete the selected item in listView when user check its checkbox

I just cant figure out how can i get the position of the selected item when the checkbox checked. here is my custom-adapter :

public class StudentsAdapter extends BaseAdapter {

private List<Students> _studetns;
private Context _Context;

public StudentsAdapter(List<Students> _studetns, Context _Context) {
    this._studetns = _studetns;
    this._Context = _Context;
}

@Override
public int getCount() {
    return _studetns.size();
}

@Override
public Object getItem(int position) {
    return _studetns.get(position);
}

@Override
public long getItemId(int position) {
    return 0;
}

class ViewHolder{
   private TextView studentId;
   private  TextView studentName;
   private  TextView studentLastName;
    private CheckBox checkBox;

   public ViewHolder(View v)
   {
       studentId = (TextView) v.findViewById(R.id.lblId);
       studentName= (TextView) v.findViewById(R.id.lblName);
       studentLastName= (TextView) v.findViewById(R.id.lblLastName);
       checkBox = (CheckBox) v.findViewById(R.id.checkBox);
   }

}

@Override
public View getView(int position, View convertView, ViewGroup parent) {

    Students item = _studetns.get(position);
    View myLayout = View.inflate(_Context,R.layout.activity_student,null);

    ViewHolder holder = new ViewHolder(myLayout);

    holder.studentId.setText(String.valueOf(item.get_studentId()));
    holder.studentName.setText(item.get_studentName());
    holder.studentLastName.setText(item.getStudentLastName());
    holder.checkBox.setTag(position);
    return myLayout;
}

}