I think your problem was that you added the "on" class to all the relevant elements ( jQuery('.staffmember') ), and not just the startup element. Waypoints are already iterating for you, as imakewebthings points out.
So your original jQuery should be:
$('.staffmember').waypoint(function(direction) { jQuery(this).addClass('on').next(); });
This should do the trick without each .
Kate
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