A great place to start would be to read the book by college audition coach Mary Anna Dennard, I Got In! The Ultimate College Audition Guide For Acting And Musical Theater. It is available on Amazon.
Mary Anna has posted a great set of free videos (Vlogs) that you can browse on her website that cover a broad range of topics that will help you get an idea for what you are facing (College Audition Coach dot com).
I posted a long list of threads from this forum that may help at the end of this post.
Auditioning for top college theatre programs is an incredibly competitive arena in which you will be well-served to use a specialized coach to help you with songs, monologues, balanced school lists, resumes, headshots, etc.
Three excellent, nationally-known college audition coaching services are:
Mary Anna Dennard - website: College Audition Coach
MTCA (Ellen M. Lettrich) - website MTCA - Musical Theatre College Auditions
MCA (Chelsea Diehl) - website: My College Audition
Each year there are posts on this forum from anguished parents with students who did not receive any acceptances due to school lists too heavily weighted with the most competitive programs, poor choices of material, lack of adequate advice on how to prepare, etc. A specialized college audition coach can help you avoid these problems. Given the effort and expense involved in the process, many consider the money to be well worth the investment.
Music Theory is the study of how to read and interpret music, covering music notation, rules of harmony, ear training, rhythm, sight singing and so forth. It really helps to have a good grounding in Music Theory if you are considering pursuing a college major in Musical Theatre, but it is not a requirement. Many MT programs do give incoming students a Music Theory test - sometimes during the audition, sometimes when they arrive on campus for placement in Music Theory classes. If you have some basic knowledge of music theory, you will likely place out of an introductory Music Theory class. To my knowledge, programs usually do not weigh the results of Music Theory tests heavily in their determination of artistic acceptance, it is generally weighted very heavily (100 percent in many/most cases) on what you show in the audition room. However, once in the major, those with prior training in Music Theory will find their way much easier than those with little or no training. College Music Theory classes can be quite demanding, and Music Theory is a requirement in every MT program.
The general consensus seems to be that it makes no difference in the odds for admission. Unifieds offers the chance to audition for many programs in a short time, but some consider the atmosphere to be a little too intense. On-campus offers the chance to see the school and usually includes tours, parent info sessions with the MT department, etc., but requires much more effort and expense.
Generally speaking, yes, artistic references are required by most programs.
There are many schools with excellent MT programs where she will likely be accepted academically. For example:
U Arts
Ball State
Baldwin-Wallace
Boston Conservatory
Carnegie Mellon (they relax their academic criteria greatly for Acting and MT majors)
Central Florida
CCM (Cincinnati)
Coastal Carolina
Hartt
Ithaca
Millikin
Molloy
Montclair
Northern Colorado
Oklahoma City
Otterbein
Pace
Point Park
Roosevelt
Sam Houston State
Shenandoah
Temple
Texas State
Viterbo
Webster
Western Michigan
Rider
Wright State
This list is just off the top of my head, and I am certainly not an expert in academic acceptance counseling. A great source of information on academic acceptance criteria for every college is the website “College Data dot com.”
Here are some past threads that may help you:
http://talk.collegeconfidential.com/musical-theater-major/2058607-current-high-school-juniors.html
http://talk.collegeconfidential.com/musical-theater-major/1880883-junior-year.html