I have a 4 year old quarter/arabian that likes to rear up dose anyone knows how to brake him of it

Amy, i have a 4-5 yr old that won't lunge and will buck when i make her?

Help! I have a 10 y/o mare. She's lovely well trained. Having trouble with her leaning on her left rein and not staying straight going right around the ring. I've owned her for several months. She was vetted before I purchased her. She's spent half her life in pasture so she's forgotten some of her original training which was in dressage. She's starting to pick it up again with the help of her trainer. However, she can't get flying lead changes and her trainer wants to fix the leaning and straightening problems first.