I recently asked two high school teachers of mine to be my main LoR writers. But later I found out that supplemental letter of recs were a thing, and wanted to ask a professor that guided me through a research project for one as well. Would this be a good idea? One of the HS Teachers I asked was the teacher for the 'helper' class for the research I did, but she didn't see the actual research process I went through. Would this be a good idea?
If you think the professor you worked with can provide a unique enough perspective of you compared to what your other teachers might have wrote I don't see an issue with asking them for one. I think you would want to ensure that this LoR is adding new dimensions to your profile and not just repeating information which can be found in your other recs. If you don't think what they write will be too different then I'm not sure if there's much benefit besides the fact that the rec comes from a professor rather than a teacher.
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