Looking at your list of questions, here are some ideas (in priority order, but note that I am not an expert and these are just ideas):
- Read Mary Ann Dennard's book: *I Got In*. It is available on Amazon. This is a solid, succinct introduction to the process and will help you know what questions to ask along the way.
- Take private voice lessons with a voice teacher who knows a lot about modern Musical Theatre and healthy pop/rock singing (a huge emerging trend in MT).
- Take as much ballet as you can fit into his schedule, at least enough to understand the basic terminology and positions. Jazz and a little tap would also be great if time permits. It can be really hard to fit dance in around an active high-schooler's schedule.
- Think about using a college audition coach during his junior and senior years, especially for help with finding and selecting appropriate monologues, monologue coaching, and guiding you through the audition process. Mary Anna Dennard and MTCA are both highly-respected nationally-known coaches/coaching services; there are others including many fine local coaches around the country. Just make sure the coach is up-to-date on the college audition process for MT. Many great local acting and voice teachers are not very up-to-date on the college audition process. Be wary of anyone who says, "Oh, he's great, he will get in everywhere."
- Summer programs are great, but are expensive and relatively limited in terms of actual duration. Programs that mostly focus on preparing a musical might not be the best choice vs. those that focus more on college audition prep and a showcase. Given the expense involved, I would personally recommend hiring a national audition coach vs. going to a summer program if financial resources are limited. However, many students would not trade their summer program experiences for anything, so your mileage may vary.
- Trying to determine the nuances of various programs is very difficult vis-a-vis, "they will take newbies," or "they prefer accomplished dancers." For every declaration I have heard such as, "that's a dance-heavy program that only takes slim builds and toned bods," I can point to a student they took who did not fit any of those attributes. I think its easier to think about, "is the overall experience offered by this program what I am looking for?"