So, here's the deal. You don't like your score, and you've carefully explored the standards and noticed the vocab standard is weighing you down. Vocab is one of those things that improves in a couple ways -- conscious effort to improve your academic lingo (in other words, wearing your fancy pants and using fancy shmancy words) and/or reading more. Grammar and conventions works in the same way.
First, here's a link to some vocab (note: it includes both content-specific vocab as well as links to academic vocab; content-specific = vocab found in a typical 11th/12th grade English course; academic vocab = words an 11th/12th grade student would use to "sound smart"). The "Vocab for the College Bound" contains the academic words. No need to dive into too many, but purely use them as a resource. One could also easily search in google "academic words for 11th or 12th grade" and you might find better, more accessible lists.
Second, Here's a link to a text we didn't read, but I had planned on including it. It's rather long, so if you go here, and scroll down (left side), you'll see the video of her delivering the speech. It's a good one! It's worth your time! I swear! Also, it's not depressing; HOWEVER, it's pretty darn cheesy. You've been warned.
Third, there are other ways for you to bring up that darn score, especially if it's connected solely to the vocab one, but here's what one way to show your level of proficiency:
1) Analyze (ANNOTATE!) the rhetoric in a provided text (short and sweet with NO essay...just identifying and briefly explaining where the speaker uses the rhetorical device -- content-specific vocabulary -- and how it's being used
2) Analyze (via annotations and commentary in the margins), using your academic vocab lingo (show you can "talk the talk" and "walk the walk" in that you know what the words means AND know how to use it)