How can an applicant understand what a highly selective college is looking for?

Applicants can find out what highly selective colleges are looking for by going to the college's admissions web page.  First look at the admitted student profile of the most recently admitted students. The profile will show you the grades and testing of the middle 50% of admitted applicants. This will give you a good understanding of the academic quality of the students the school is looking for.  Additionally, schools will often list accomplishments of their admitted students.  You can often find lists of these accomplishments.  Usually highly selective colleges and universities are looking for students who have challenged themselves academically and have made a significant contribution in another area outside of their school work.  Students do not have to be in every club and activity to be competitive, but they do have to have a significant committment to at least one or two areas outside of schoolwork.  And those are key words, "outside of schoolwork."  The activity doesn't have to be a school related activity.  It can be a sport, a musical instrument, a job, taking care of a family member, or being in a school activity. You get the picture.  When all else fails, call the admissions office of the schools you are considering. Ask them what the profile of a competitive applicant is. Ask them if students need to have participated in a certain caliber of competition or activity in order to be competitive.  These professionals are there to help you with the admissions process.