Checkboxes often precede their labels, but don't be confused. The "id" attribute still goes with the control, and the "for" attribute still goes with the label.
<fieldset>
<legend>Your dog's favorite foods:</legend>
<input id="kibble" type="checkbox" value="kibble" />
<label for="kibble">Kibble</label>
<input id="chow" type="checkbox" value="chow" />
<label for="chow">Chow</label>
<input id="steak" type="checkbox" value="steak" />
<label for="steak">Steak</label>
</fieldset>