You still haven’t said what you plan to study and major in if you were to get accepted to Wesleyan. Notice the wording below from Wesleyan’s website – it says some students supplement with “art, music, or scientific research.” It does not say “art, music AND scientific research” as if students can and should supplement with all three. By saying “OR” it indicates that one type of supplement is all that is intended. The rest of the wording supports this conclusion. It says the supplement should represent a “special accomplishment or interest, or reflect an educational goal.” Notice the word OR again, not AND.
If you submit science, art AND poetry supplements, it indicates that you don’t have any special interest or educational goal. I also wonder whether any of your planned supplements represent a special accomplishment. If you won a national or international award with one of them, that would be a special accomplishment. If you plan to major in one of these subjects, then that would be an educational goal. If one is a passion that you plan to continue while at a university (as a hobby or as part of club, perhaps), then that could be a special interest.
If none of your planned supplements fit these categories, I wouldn’t submit them. If only one fits, then I would submit only that one. Obviously, this is all just my opinion and interpretation, so feel free to submit all three if you think that is best. I wouldn’t want you to only submit one or none and not be admitted, and then think that the reason you were not admitted was that you did not submit all three supplements. You might also think about it and decide to choose a different supplement altogether. Only you can decide in the end how to package your application.
From Wesleyan’s website:
APPLYING TO WESLEYAN
ART & SCIENCE
Although not required, some students supplement their application with work - such as art, music, or scientific research - that represents a special accomplishment or interest, or reflects an educational goal.