If the situation is critical, ask your professors for some extra credit.
Usually, they have this option open for everyone and announce it at the beginning of the year each year. But they're often willing to make an exception, especially seeing that you'd like to put some effort into it.
Some of the courses will have to be retaken - I don't know your situation. If you're really desperate with a load of assignments hanging around, look through Omnipapers. They don't sell papers, but they might help with some reference material.
Did you think about dropping some of your classes? If you're an international student, you might have visa problems if you drop out of college.
Good luck to you!
