First of all, Happy holidays to all of you! 
GPA: 3.76 uw, 3.90 w (School weights weirdly)
Rank: 36
AP Classes: 1 soph year, 2 junior year, 4 senior year; 7 total
AP tests: World H:4, USH:5, English Lang:5, Calc AB(Self Study):4
SAT:1550; 780m 770e
Extracurriculars: ~70 hours of volunteer work, Boy Scout (Life Rank), 3 years in Spanish Honor society, marching band for four years,
work experience: none
Essays: Decent (while no one proofread them, I think my writing accurately represents me.)
Extra information: Catholic
Demographics:
Gender: Male
Ethnicity:White
SAT II: 800 Physics, 780 Math II, 740 World History, 750 Chem
I did visit ND
Teacher Recs: One teacher used a template, so not as good as they could be
Happy Holidays to you too:) I would say that your AP/SAT/SAT II test scores are all very good. What might hold you up is your GPA. It’s a little lower than NDs usual range. If your high school truly does weight weirdly, is there a way to have your guidance counselor address that in an email or phone call to ND admissions so that they are sure to get an accurate reflection of your performance? It’s hard to tell what your rank of 36 represents without knowing the number of kids in your class. Also, if you haven’t submitted yet, I would suggest you have someone proofread your essays. That’s great that you feel they accurately represent you, but you also want to put your best foot forward. Sometimes in this world where everyone has good grades and good scores, the essays can really make a difference. Good luck to you!
@waitingmomla There is no reason for the OP’s guidance counselor to contact ND admissions to explain the HS grading system. Every HS sends a school profile with that information (and more details on the HS) along with each transcript. College admissions officers are used to dealing with many different types of HS grading systems.
@MarlesSpaceman You look like a competitive applicant if you are at/near the top of your class. Compare your stats to the ND profile to decide for yourself where you stand. http://admissions.nd.edu/apply/admission-statistics/ Good luck.
Yes, @happy1 is correct. My bad, I wasn’t thinking. Admissions know all high schools weight differently and they take that into account. For some reason I was thinking of circumstances unique to you, but I realize that’s not the case here.
But for the purposes of getting the most helpful feedback here, it would help posters to know your percentile rank. Because that would put your GPA in better perspective – that GPA with a 5% rank is a different situation then the same GPA with a 25% rank. So knowing the percentile helps to better understand the GPA, whatever the grading system.