If you struggle to land a 1 1/2 toe turn cleanly, try starting the turn leaning slightly BACK, which tends to help you come out of the turn ready to step cleanly out of it. Would work for 1/2s and 2 1/2s as well.
Also, if you get the bad turn syndrome where they start getting all weird, be sure to practice some turns going in the other direction. It helps straighten out your brain!