How do I execute a DatePicker.

JavaScript runtime error: Object doesn't support property or method 'datepicker'

<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
    <script type="text/javascript">
        /* create an array of days which need to be disabled */
        var disabledDays = ["2-21-2010","2-24-2010","2-27-2010","2-28-2010","3-3-2010","3-17-2010","4-2-2010","4-3-2010","4-4-2010","4-5-2010"];

        /* utility functions */
        function nationalDays(date) {
            var m = date.getMonth(), d = date.getDate(), y = date.getFullYear();
            //console.log('Checking (raw): ' + m + '-' + d + '-' + y);
            for (i = 0; i < disabledDays.length; i++) {
                if($.inArray((m+1) + '-' + d + '-' + y,disabledDays) != -1 || new Date() > date) {
                    //console.log('bad:  ' + (m+1) + '-' + d + '-' + y + ' / ' + disabledDays[i]);
                    return [false];
                }
            }
            //console.log('good:  ' + (m+1) + '-' + d + '-' + y);
            return [true];
        }
        function noWeekendsOrHolidays(date) {
            var noWeekend = jQuery.datepicker.noWeekends(date);
            return noWeekend[0] ? nationalDays(date) : noWeekend;
        }

        /* create datepicker */
        jQuery(document).ready(function() {
            jQuery("#<%=TextBox1.ClientID%>").datepicker({
                minDate: new Date(1900, 0, 1),
                maxDate: new Date(2100, 12, 31),
                dateFormat: 'DD, MM, d, yy',
                constrainInput: true,
                beforeShowDay: noWeekendsOrHolidays
            });
        });
    </script>