Sucks for you, maybe you should learn to write better.
I've got a degree in English, I had to put up with idiotic groups, as well. Out of the hundred or so unique papers I've read, maybe two or three were good, three or four were at least readable, and every other paper was the stupidest piece of shit I've ever read (let's presume it's possible for multiple papers to be the stupid-est).
These were written by people nailing A's in classes, even grad students (I only have an undergrad degree; some grad students had to take some of the upper-level undergrad classes I had to take) which shocks the shit out of me. I busted my ass on my papers and I'm a damn good writer; makes me sad to see terrible fucking writers getting A's because they talk to the teachers occasionally, visit them after class, etc... Honestly, I feel bad for most of the teachers because a lot of them were too nice and fell victim to pity and empathy. I'll also assume they also have unwritten 'quotas' / have to maintain a level of non-scrutiny from harshness in order to stay employed.
Anyways...
How will you know if you're a good writer? Start writing stuff to screw with everyone else in class, then let subtly let it be known that you're just writing it to screw with them. I did that for an entire class; every paper I wrote was something written to screw with the rest of the class (ie: page long sentences, insane and thought provoking ideas, etc...).
When anyone asks you the question "OMG WHAT DID YOU MEAN BY THIS," just sit back and say, "I don't know, what do you think it means," or, simply, "I don't know," while cracking a slight grin. Do the same if someone gives their interpretation of your work and seeks your assistance in determining if their response was "correct." Basically, act like a psychologist in a movie and keep turning everything back around.
As an aside, I highly doubt you have the time to pull this off (in the unlikely event you have the talent); it takes a LOT -- you really have to know what you're doing, have to have a substantial amount of time to do it in order to write perfectly, and you have to have the acting ability to pull off any kind of peer/class-wide reads, reviews, or "sharing" (for lack of a better inclusive term).
In the class in which I did this for every paper, the teacher caught on after the second paper (could tell from her comments); she probably found it as amusing as I had. I think one or two other people caught on by the end of the fourth paper, but nobody else did.
P.S. Everything I refer to happened in English classes, with other English majors who had progressed about the same amount through their degrees as I.
P.S.S. You probably don't know your ass from a hole in the ground since I just noticed you complain to your teacher. Stop being a pussy and do what I did: do every project yourself and/or edit everything else does yourself. If you're really as good as you think you are, your group mates will typically accept the changes because they realize what you modified / did was necessary or, at least, better. Just be sure to be tactful in bringing up your changes or you'll hear a bunch of whining (never had this happen to me). Also, your teacher doesn't want to hear your bullshit; stop bitching to them to try to get pity/sympathy out of them (you would get it, most likely, but ask yourself if you really want the undeserved grade or if you want to man up).