[chellas88]

Так не катит?

<button id="1" class="btn">btn1</button>
<button id="2" class="btn">btn2</button>
<button id="3" class="btn">btn3</button>
<div class="block1">block 1</div>
<div class="block2">block 2</div>
<div class="block3">block 3</div>

.switched{
  background: red;
  color: #fff;
}

$(function(){
	$('.btn').click(function(){
  	var item = $(this).attr('id');
  	$('.btn').removeClass('switched');
    $('#' + item).addClass('switched');
    $('div').show();
    $('.block' + item).hide();
  });
});