Chance me for MIT, UCSD, UChicago, UIUC [SC resident, 3.81 UW, 34 ACT, math/cs, single parent household, <$30k (35000 SAI)]

I’m sorry to hear that. (My own daughter is having a very frustrating time in one of her classes right now.)

Challenges like this would be something your counselor may be able to explain in their letter.