I have a table with a bunch of td with the classes markTD and they each have a different integer for the attribute value.  I would like to click the button called mark and change the color of just 1 of the td.
 $('#mark').click(function(){
    var h2 = parseInt($('#h2').attr('value'), 10);
    //h2 returns the number 3
        $('#markTD').find('value',h2).css("color","red");  //this is the line that's not working
}
HTML
<table id='markTable'>
<tr>
    <td>Question number:</td>
    <?php 
        $q=1;
        while ($q <= $num_rows){
            echo "<td class='markTD' value='" . $q . "'>" . $q .  "</td>";
            $q++;
        }
    ?>
</tr>
</table>