do i really need this?

Motivation increases when you visit the professor during office hours. Ask questions when you visit. Ask him how the course will help and let him explain. Maybe you'll make friends, even so he'll know who you are and it might help in the long run. Because you know who he is it will be easier to motivate yourself.

What is the course? What is your major? What is your chosen career? I think I would need to know these things before I could give you advice

In your path through college there are going to be courses that are required for graduation and don't seem to directly impact the future career you want to have. Typically colleges use these courses to provide a breadth of experience and exposure in different areas to help make students well rounded. Being in one of these classes, with a professor that you don't click with can make it a challenging experience.

The first thing I would focus on is what can be in it for you. What can you benefit from this class, from this experience? It may not be easy at fist to find this, but it's there. If nothing else, it will help you with difficult situations in the future. There will be bosses, colleagues, lecture topics, and other things that you have to simply deal with.. this might be the starting point for you to prepare for those things. Which either way works best for you, once you find the positive aspect you can learn your motivation for the class will begin to increase.

I would also recommend networking with others in your class. If this is a required course there are other students in the same situation as yourself. They are there, feeling and thinking the same as you. Form a social network in the class for study groups or hang outs. Make sure you use these sessions to focus on the material and not turn them into vent sessions about the class.

You say the course with the boring prof is core; you also say it's required for graduation. In some schools, some core courses are interchangeable. That is, you could substitute one core course for a related core course. If you cannot substitute, I suggest getting some other students in the course to form a study group to help each other out!! Having mutual accountability can be very motivating.

Have you spoken with your academic advisor about this issue? It might be helpful!!