How to install jQuery Plugin into WordPress Theme

Hi, I’m trying to add this jQuery pluginto my WordPress Child theme of Responsive. The problem is after some heavy research, I got lost and have no idea how to add an external jQuery to a WordPress theme.

Here is how I’ve tried to do that without success:

1. Html identical as in the plugin’s exemple.

2. functions.php.

<?php
function modify_jquery() {
    if (!is_admin()) {
        wp_deregister_script('jquery');
        wp_register_script('jquery', '//ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js', false, '1.10.2');
        wp_enqueue_script('jquery');
        wp_register_script('modernizr_script', get_stylesheet_directory_uri() . '/js/modernizr.custom.js', array('jquery'), false, false);
        wp_enqueue_script('modernizr_script');
        wp_register_script('grid_script', get_stylesheet_directory_uri() . '/js/grid.js', array('jquery'), false, false);
        wp_enqueue_script('grid_script');
    }
}
?>

3. sidebar-home-widgets-triple.php – at the end of the template file.

<script>
var $ = jQuery.noConflict();
jQuery(document).ready(function() {
    Grid.init();
});
</script>

Many thanks!