 
  
   
  
  <button id="open">Открыть</button>
<div id="form">
  <form action="#" method="post">
    <input type="text" value="" placeholder="найти" />
  </form>
</div>#form {
  padding: 20px;
  background-color: #000;
  display: none;
}$(document).ready(function () {
  var searchBlock = $('#form');
  $(document).on('click', '#open', function () {
    searchBlock.slideToggle();
    return false;
  });
});