ABSOLUTELY! Teachers AND Coaches can be bullies! I have seen it first hand and my children have experienced it. Adults that DON'T feel bad about belittling, degrading, yelling at or in a child's face (especially a child that is not your own), calling them lazy, calling them losers, cussing at them when they may not hear that type of language at home, telling them they DON'T have to be a leader...the list is SO long...if an adult that is suppose to be a leader, a person children look up to and they do any of the above or anything else extreme that is damaging to a child's self esteem...YOU ARE A BULLY and you need to seek some counseling and shame on you.
If you see the mistreatment of children, even if they are not your own and you do not say anything, shame on you too, you are just as much part of the problem. Nothing changes when people stay quiet. It saddens me how so many will turn the other cheek because they feel that it's not their business or better yet, they feel like they don't need to say anything because it is not directly affecting them or their children. Guess what, if a child or children are being verbally or mentally abused, and bullied by a teacher or coach, that changes the abused child's behavior and attitude and in the grand scheme of things it changes how they interact with your child, it molds what type of adult the child will turn into.
If your child's behavior has changed since they have been in school, don't be so quick to blame them, talk to them and find out what is going on, they could be dealing with some issues that are out of their control. Your children need you, you are their best advocate. NO ONE, and I mean NO ONE is going to go harder for your child then you. There will be lots of people who don't care, there will be lots of people who do care, but it is still not the same as the child's parents advocating for them and supporting them. I had a teacher tell my son, while in a conference that she will never care as much as me or his dad will. I get what she was saying, but the delivery could have been better, and if it were me I would have never said anything like that to a 7 year old. All a child hears is the negative...so the child ends up thinking his/her teacher does not care about him/her. We ALL make mistakes but leaders of the community such as teachers and coaches are held do a different standard. They need to choose their words carefully and be mindful of how their behavior and attitudes may affect the very children that they are in a position to guide in a positive way.
If it makes you feel good to try and live out your dreams through your team as a coach, if it makes you feel good to talk down to children in your class...you have issues! As cliche and corny as it may sound, the children are out future and we need to protect them and guide them with love. You big bullies that yell at or talk down to children, get it together. Remember it is not about you! Put the children first! If you do not have the best interest of ALL children at heart that you spend large amounts of time with, get a new career! If you are volunteering, find another field of interest that does not involve children.