Dear Frustrated, The dilemmas you describe are not unusual, in fact, very typical. Ring sour school horses. Here are a few ideas that come to mind as I read the descriptions. POA mare: I'd get rid of her. I have no experience with the implants and it is possible that by the time you can get her sold, they will be working. However, I think we far too often blame mare problems on hormones. I have made an effort to eliminate all mares from my school horse string. It is my opinion, after more than 20 years of dealing with school horses that mares sour more quickly, learn more controlling and manipulative behavior and induce more bad behavior in the other horses. This makes a lot of sense if you think about it. Mares are the controllers and protectors of the herd. These manipulative behaviors are inherent for them. Mares are also more inclined to build a relationship with a rider (after a period of testing, the mare usually will come around and learn to like the rider), which bodes well for an individual owner, but not as a school horse. I have also noticed that geldings that are otherwise perfect will get territorial and fussy when you bring a mare into the ring. Since this mare's bad behavior has escalated to the point of nipping and pinning ears, I'd say get rid of her and replace her with a gelding. Appy mare: you may want to try a bosal or side pull to see if that keeps her from going behind the bit. If she is doing that just to get away from hard hands, you can hardly blame her. But if she is going behind the bit in order to take control, that's another story. If she is getting out of control, get rid of her. As for the crow hopping, if she is otherwise pretty good, then she is probably just a little cold-backed. My best old beginner horse is this way. If I know he hasn't been cantered in a while and I am going to need him to canter, I just hop on and canter him first until any humpiness subsides. The problem with these horses is that sometimes they will hump when the rider gets off balance, which a rider is prone to do when learning to canter. So while this horse may be good for walk trot, once the student is cantering, you may need to use another horse. But realize that you are possibly setting yourself up for greater liability, because if someone falls, and the horse was known to have bucked before, this would look bad for you. Some of the behaviors you describe are just tricks the horses have learned that they can get away with. What you need is to have a regular schooling program for them. If you have an intermediate or above rider, offer to let them ride in some lessons free for the purpose of schooling the lesson horses. Let the horses stand on the rail or walk, but when they try to come into the ring, put them right to work with trot and canter circles. As soon as they offer to go to the rail, let them walk or stop. Soon they will learn the rail is the easy place to be. All school horses need regular maintenance in their training. A couple of these horses sound like they may be beyond messing with. You can't really unlearn behavior, so once a school horse has learned evasive techniques, and been successful with them, it is tough to reprogram them. I watch my school horses like a hawk. At any time I think it is turning into a negative experience for the horse, I make a change. I ruined a very nice Morgan mare by not recognizing her distress in time. By the time she was employing evasion techniques (in this case, running off and ramming the other horses) it was too late to change her, she had learned too much about different types of students and what techniques worked best on them (typical mare problem). I sold her and she is an excellent family horse, she just wasn't cut out to be a school horse. It is the nature of mares to want to build trust in their herd mates (the rider) and as a school horse this can't happen and they too often get betrayed, which leads to ring sourness. With the real lazy horses, I find I can control them from the center of the ring. If they know I will come after them to enforce the cue, once they see I am watching, they'll usually hup-to. But you have to consistently enforce this. It sounds like you need to do some schooling on these horses with an advanced student, think about replacing some of them, and watch their training closely. Another thing I do not do is let people ride my horses outside of my supervision. I watch my school horses closely and consider them one of the biggest assets of my business. And if you think you're frustrated, just imagine how they feel!