I think an index of services offered, special distinctions that make a school "Asperger's friendly", etc would be the most useful.
I like the idea of a top 25 list, although since ASD individuals obviously vary, that is a really subjective distinction. Still, it would give you a place to start with providing the type of index noted above, which will help future students understand what some of the criteria are and what to ask about for schools not on the list.
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Mom to an amazing young adult AS son, plus an also amazing non-AS daughter. Most likely part of the "Broader Autism Phenotype" (some traits).