Drawing, especially the ability to quickly represent an idea.
I think that covers rounds one and two. As for three I don’t think anything is a total waste of time, certainly there are subjects that seem that I will never use but one never knows.
Good luck with the degree, what area(s) of design are you interested in?
Tim

Conditional of the kind of design you’re interested in, but if you plan to do print work for the most part I’d give the following:

1.
The 3 P’s – Prepress, prepress, production. If you want to make it as a designer you have to start somewhere and one of the best ways to show that you deserve those creative projects and are worth hiring is file handling. It’s surprising how many recent grads do not know how to properly package a file for the printers or know the finer nuances of production work. Some may argue that there’s great people that only do this their entire career, and it’s true not every designer will be great and will find their niche doing one of these very important jobs. Knowing these skills well will at least get your foot in the door at a local print shop; up to a large studio or agency. It improves your speed on the computer, forces you into the habit of checking details and will help you immensely as you further your career.

2.
Paper first. It’s the computer age and there is a strong urge to not to roughs/comps/ sketches on paper. It’s a skill I find that gets over looked. Learning to draw is a great skill that everyone should try to work on.

3.
Learning isn’t really a waste of time, sure you’ll find things that are stupid or that you already knew, but overall there’s nothing that comes to mind that was a ’complete waste of time’.