Question: D1
 D2
 D3
I need to change just the values between `<span>` and `</span>` D1, D2, D3 with JQuery, with new values like X1,X2,X3 with JQuery.

Answer: 
use

```
$('#navigation').find('span').each(function(){
    var $this = $(this);
    $this.text(function(i, curr){
         return curr.replace(/D/, 'X');
    });
});

```

That would fit exactly your example.
`$('#nav-d1 span').text('X1')` would change `<span>D1</span>` to `<span>X1</span>`