I'm a very bright person so don't think I'm stupid or something. I take multiple advance classes and ace dem I have always struggled with English. Like instead of getting an A like I do in all of my other class I get B's. Now I'm a very unsirious person and I'm always havin fun but for some reason I can't get past a B+. please leave tips in comments if ur good at English.

When you say things like "I ace dem" do you know the word you want is "them" but just use "dem" as some kind of abbreviation, or do you think "dem" is what everyone else types and they're all wrong with "them"? Or do you not notice?
Also, things like "unsirious" which would strictly be spelled "unserious" but isn't technically a word, anyway. It seems odd to use a word like "serious" and then negate it when there are plenty of antonyms of serious (i.e. trivial, frivolous, fun, lively, engaging, gregarious).
I'm not getting at you; I'm just wondering if you consider these things. If not, your English may improve by taking them into consideration.
My English isn't the best so feel free to take this with a pinch of salt.
English has always been my forte, as well as just about any subject that requires a high level of verbosity and reading comprehension skills. So go read, and not crappy books like Twilight but serious novels. Pay attention to the way in which the author speaks, pay attention to the spelling and strive to speak the way that the author speaks in an intelligent novel.
It is said that well read people are often more articulated than the less read, so go get at some literature!