How to Add Active Class to a Navigation Menu Based on URL?

How to Add Active Class to a Navigation Menu Based on URL?

Alright guys I am new jQuery and don't dabble to much in this stuff mostly just html language. But, I need to know how to add an active class to the li element of the navigation. I need to be able to do this as I am switching over my static html pages to a more dynamic environment where information is called from the server to help me in maintaining the site.  So here is what I have so far: The page that I am working with / testing is the home page found at http:www.bomstudies.com

My jQuery Code: 
Script Tag:
<script src="js/highlightNav.js"></script>

Code inside .js file:
$(function() {
     var pgurl = window.location.href.substr(window.location.href
.lastIndexOf("/")+1);
     $(".sf-menu a ").each(function(){
          if($(this).attr("href") == pgurl || $(this).attr("href") == '' )
          $(this).addClass("active");
     })
});

HTML Nav Code
My Nav / Menu Only Showing up to the first li element:
<nav class="menu-wrapper">
    <div class="container menu-container">
            <div class="menu-height">
                <div class="consider-boxed">
                    <div class="row-fluid">
                        <div class="pull-left">
                            <nav>
                                <ul class="sf-menu" id="nav"> 
                                    <li class="first-level-li">
                                        <a href=" http://www.bomstudies.com/index.html" class="first-level-link active">
                                            <div class="menu-icon"><i class="icon-home icon-large"></i></div>
                                            <div class="menu-item-wrapper">
                                                <div class="first-level-li-text-link">Home</div>
                                            </div>
                                        </a>
                                        
                                    </li>
                                          Continue on etc not shown here. 

Let me know what I should change or if there is a better way I have been working with this for hours and have finally trying my luck here. Any help is greatly appreciated - thanks!