I just want to clarify: you are not looking for a school that specializes in the arts (like Walnut Hill), you are looking for an overall good school that happens to have a strong music program for the sake of child 1 and academic support for the sake of child 2.
I think you should avoid the usual high pressure choices. You want child 1 to have time to actually play the violin, and you want child 2 in a more supportive environment where child 2’s strengths will also shine.
I would worry less about the number of orchestras and more about what is offered to the individual. For example, at some schools without a full orchestra, they off level based ensembles. Look for on campus private lesson opportunities. Or, look into whether the music department has students in NEC Prep.
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