In my district, everything is determined in middle school. Students taking gifted track, advance math track, testing out of regular language courses, getting into clubs and EC, doing summer/online courses, parents knowing how to avoid GPA killer courses/picking GPA booster courses when doing academic conferences for HS while in 8th grade, taking SAT prep for TIP/CTY, playing sports, doing science fairs, are the ones who end up eligible for elite colleges. Only one or two outliers may turn out to be an exception but for 99.9% it is stamped before you even start 9th grade.