In regards to All State, it depends entirely on the type of school you are applying to, the state you are in, and also the instrument.
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If you are applying to a top conservatory (Juilliard, Colburn, Curtis, etc.) they could care less about All State. In fact, it probably would look strange to them. On the other hand, lower level conservatories and especially universities (including Ivies) really like All State.
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If you are a string player, All State is not of as much significance as it is for winds/brass, who need to obviously demonstrate more orchestral experience. Generally, higher level conservatories want to see string players doing a wider range of solo and chamber music opportunities than just orchestra. For the same reason, top conservatories don’t look at orchestra summer programs for string players as highly as they do for winds/brass. (NYO might be an exception to this, but generally top-level string players aren’t going to places like BUTI or Interlochen.) I don’t know about choir, but I suspect All State is viewed as more important.
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Your state matters a lot. In my state, each region sends an equal number of kids to All State. Since there are really only one or two good regions near the city, the level of the ensemble on a whole is pretty low. On the other hand, in some states like Texas, it is much more of a high level experience.