Post Highschool Plans?

Can your senior year have any factor on your GPA and all that? Are there any colleges that accept students after the 1st semester of senior year? I'm not aiming for a top notch college because I decided ages ago that I'd rather be comfortable than rich.I just want to have a job in the field I want and be happy doing my job. My Gpa isn't horrible or anything, it's a flat 3.0 unweighted. I've done things in and out of school that are noteworthy. I may even consider transferring to a university from a community college. Any advice would be appreciated