Scott Hanselman has a post on the three things he learned about software after college and has asked for others to chip in. Here are my thoughts...
1. Boolean logic can help prove a statement.
2. Comments should be added to code for clarity.
3. Projects should be completed on your own.
Out of College:
1. A test, or set of tests, is much clearer at proving that code is correct.
2. Good code needs well-named, decoupled, highly cohesive parts, NOT comments.
3. Asking for help does not mean that you are weak, it means you have the strength to admit that you cannot accomplish something on your own.
Disclaimer: I have not actually completed college (YET) but have taken many college courses.