I know how you feel. Back then, I would've done anything to be in middle school, because I thought different classes and all would be cool. My elementary school had kindergarten through sixth grade, so while I was in sixth grade in elementary, all my friends were in middle school. They kept on bragging on how much middle school rocked, which made me want to be in middle school even more. What was I thinking?
These days, I would do anything to go back to elementary. Middle school really sucked, let alone high school. -.-
You just have to stay strong and keep going, pretty much. Compared to high school, though, middle school was so much better. Enjoy it while it lasts. When you hit your junior year in high school, things start to explode. TONS of tests and even more drama. Senior year just gets even worse. I'm so happy that I'm done with all that. I get to go to college now 8D
I mean, it probably just means more studying, but it'll be nice for me to finally study and focus on a career, while in high school, you just basically study and take tests to get into college.
So, anyway, basically, my advice for you is to keep going. Don't worry about all the stupid boyfriend/girlfriend drama, "popular" groups, bullying.... just worry about your own friends and grades for now ^3^ It'll get worse, so you have to learn to ignore it. Best of luck to you~