[Vlasenko Fedor]

<div id="test">
  <div>0</div>
  <div class="play">1</div>
  <div class="play">2</div>
  <div class="play">3</div>
  <div class="play">4</div>
  <div class="play">5</div>
</div>
<script>
  window.onload = function () {
    test.onclick = function (e) {
      var el = e ? e.target : window.event.srcElement;
      while (el !== this) {
        if (el.className == "play") {
          alert(el.innerHTML);
          break;
        }
        el = el.parentNode;
      }
    };
  };
</script>

разбирайся с примером