thumnail images not fadetoggling but enlarging to original size

thumnail images not fadetoggling but enlarging to original size

Hi I have just started learning jquery so please help me out here. 
I have a group of images under div's eg.2012images,2013images etc,
all these div's are wrapped in a wrapper displayed as thumbnails at the bottom of the page.
What I want is when the user clicks on 2012images ,these images should all display in the center of the page as a large image as a FadeToggle and stop at last image.

I have written the code as such:

<style>
.enlarge{
          width:75px;
          height:75px;
          position:absolute;
          margin-top:5px;
          margin-left:auto;
          margin-right:auto;
}
.2012images{

cursor:pointer;
}

</style>


<div class="wrapper">
      <div class="2012images">
               <a href="#"><img src="#"></a>
                <a href="#"><img src="#"></a>
                <a href="#"><img src="#"></a>
        </div>
<div class="2013images">
               <a href="#"><img src="#"></a>
                <a href="#"><img src="#"></a>
                <a href="#"><img src="#"></a>
        </div>
</div>

<script>
  function InOut( photos )
{
 photos.delay()
     .addClass('.enlarge')/* this will position the group photos in the centre of the page*/
     .fadeIn('3000')
     .delay('4000')
     .fadeOut('3000', 
               function(){ 
                   if(photos.next().length > 0)
                   {InOut( photos.next() );}
                   else
                   {InOut( photos.siblings(':first'));}
                         
                 }
             );


$(function(){
$('.wrapper').on('click',(function(){
    var $this=$('this');/* selecting inside div i.e.2012images or 2013images*/
InOut( $('$(this):first') );
}));
});

</script>



But everytime I click on 2012images the images enlarges to its default size and does not do anything else. Can anyone help me please. How should I code to stop this auto enlargement and instead do a FadeToggle based on user selection ..thanks in advance.