element.html

<link rel="import" href="../bower_components/polymer/polymer.html">
<link rel="import" href="../bower_components/iron-menu-behavior/iron-menubar-behavior.html">

<dom-module id="broadway-menubar">
    <template>
        <div class="selectable-content">
            <content></content>
        </div>
    </template>

    <script>
        (function() {
            Polymer({
                is: 'broadway-menubar',

                behaviors: [
                    Polymer.IronMenubarBehavior
                ]
            });
        })();
    </script>
</dom-module>

usage.html

<broadway-menubar attr-for-selected="data-route" selected="{{route}}">
  <a data-route="choose" href="/" on-click="onDataRouteClick"><span>Choose your place</span></a>
  <a data-route="soundtrack" href="/soundtrack" on-click="onDataRouteClick"><span>Choose your soundtrack</span></a>
  <a data-route="relax" href="/relax" on-click="onDataRouteClick"><span>Relax</span></a>
  <a data-route="exercise" href="/exercise" on-click="onDataRouteClick"><span>Exercise</span></a>
  <a data-route="massage" href="/massage" on-click="onDataRouteClick"><span>Massage</span></a>
</broadway-menubar>