Detach and append on checkbox selection, using array built from variables of element ids

Detach is working fine but not append. I thought the array was building right but when appending again, array is undefined. Also, I will need to keep from adding the same element to the array if unchecked multiple times.

JSFiddle: http://ift.tt/2AUV4Ic

$(document).ready(function(){
var restoreMe = [];
 $("#studentCourses :checkbox").change(function() {

    var courseid = $(this).attr('id'),
        row = $(this).closest('tr'),
        cell = row.children('td').eq(3),
        course = cell.find('input');

    if($(this).prop("checked")) {
        //var rm = $.grep(restoreMe, function(e){ return e.courseid.to_string == courseid.to_string; });
        row.css('color', '#000000');
        restoreMe[courseid].appendTo( cell ); 
        //rm[0].courseid.appendTo( cell ); 
    } else {
        row.css('color', '#c0c0c0');
        restoreMe.push({courseid: course.detach()});
        }
});
});