HTML 

<div id="navigation">
  <ul>              
    <li><a data-section="our-mission" href="#our-mission">Our Mission</a></li>
    <li><a data-section="what-we-do" href="#what-we-do">What We Do</a></li>
    <li><a data-section="how-to-help" href="#how-to-help">How To Help</a></li>
    <li><a data-section="get-involved" href="#get-involved">Get Involved</a></li>
    <li><a data-section="contact" href="#contact">Contact Us</a></li>
  </ul>
</div>

JavaScript 

$("navigation").on("click", "a", function(event,element) {
  event.stop();
  section = element.readAttribute("data-section");
  Effect.ScrollTo(section, { duration:'0.6', offset:-50 });
});