Another cool way to do this in PHP:
<?php
if ($myCondition == true) {
?>
<a href="signup.php?ClassKey=<?php echo $row_rsEducation['ClassKey'];?>">signup</a>
<?php
}
// the rest of your php goes here...
?>
Don't forget that this method can be used too. This is especially helpful if you have more complex HTML (like 50 lines), and you don't want to have to echo each line.