slideToggle
HTML
<script src="//cdnjs.cloudflare.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<p class="text">Hidden Text</p>
<a href="#"><div class="expander">Click Here</div></a>https://jsfiddle.net/#save
JavaScript
$(document).ready(function () {
$('.text').hide();
$('.expander').click(function () {
$(".text").slideToggle();
});
});