ya want to get into a really good college or are you looking to go to a mail order school? If its he second then I guess failing several courses wont be dealing death to your prospects.
You better have really good SAT's and a convincing story about being ADHD or dyslexic to convince your admissions committee that youre worth further consideration(we are usually stopped head on with dyslexic or ADD kids because they can be real treasures).
In the past I sat on admissions committees and , when the school has a semester max quota and the reality is that we get applicants over 25 times the admissions. SO we quickly weed out many of the poorer
performers unless there are some mitigating circumstances and they show some hidden talents.
Not caring about history?or art? These may indicators