First you need to ask yourself several important questions. Am I a good rider? Do I know how to care for a horse in every way possible? Can my family afford a horse? If you answered no to any of these questions then you shouldn't own a horse yet. If however you have been taking regular lessons, know adequate horsemanship skills, and can afford the costs then possibly you're ready. You can show your dad how mature you are and begin saving up any spare money you have. Once he sees you are really taking this seriously he might consent to it. Otherwise ask him if you could half-lease a horse to get a feel for ownership and the cost of owning. If he feels you can handle it I'm sure he will soon be helping you pick out a horse of your own.
Tell him that you will take care of it and viola!
No need 2. Twitter is useless.
Say "Dad I have a new friend and she/he asked if I could go to there house?"
convince*
Cut his head off
You could tell his that it's your body, not his.
In a few years you'll be 18 and can just let them know.
My dad has a PS3 that he virtually never uses. And i have no other game systems. He keeps the PS3 in his room, how can I convince him to move it to the living room so everybody can enjoy it?
Just keep asking her about it. It actually took me three years to convince my mom and dad to let me get my bellybutton pierced.
You can't. Or you could possibly find a hypo-allergenic cat.
You can barter with your dad to let you take your frog over winter break. Offer to do chores or other things to be able to take frog with you.
Nothing. Your Mom's decision is based on your Dad's behavior, not your behavior. Therefore, nothing you do or say is of any consequence to the situation.