Mac N Seitz, KCSC Blaze, Building Champions, and Prodigy are your top organizations. But just know like all big organizations, there are various level teams at each age group. Just because a team has a good organization name on their shirt does not mean they are a good team. Mac N Seitz has some really good teams and some really bad ones and they all pay about the same money wise. All of these will have training facilities and private lessons available. Mac N Seitz is probably the biggest but they seem to drop off when you get to the older guys. Right now I would say Building Champions has the best high school age teams excluding the Kansas City Royals Scout Team. If your child gets a chance to tryout for this group, it is one of the premier chances around because of the overall experience and exposure. They will have a 16U and 17U team this summer as far as I know. Lived there the past three years. PM me for more info on specifics.