G. Mark’s Answer
Class -- in general, any class, including college -- tends to be a predictable environment with individual contributions as the rule. With some exceptions, you're responsible for your own success. If you're on a team, you can sometimes just point to the others that failed to support the project.
If you work for a company, the important part is getting the project done. If you have to help others on your team, fine. If you can find out that someone else has already solved the problem you're trying to fix, great. It doesn't matter who gets the real credit for getting the problem solved, just solve it. Customers won't care if Joe or Bill fixed X, just that it got fixed. And if Joe can blame Bill, the customer doesn't generally care.
Another change is the idea of coming up with really cool solutions that are new and different but don't contribute to the bottom line. In class, that's often congratulated. In business, not so much.
In class, if you're generally hard to tolerate by other students, you can usually get by. In business, causing a toxic atmosphere hurts the workplace.
Those are the major things I learned.