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There's a corner of the Internet called studyblr, where students post pictures of the notes they've taken for a class. This BuzzFeed story says more, but, basically, they're amazing.
Creating notes like these takes a ton of effort. Does all that effort pay off in terms of learning? I'd say yes and no. (I'm talking theoretically, here. By the way, I don't have specific research on this topic.)
Organization
A beautiful page of notes is clear, concise, and well-organized. There is an endless supply of research showing that organizing your thoughts helps you learn. So in this case, if you take a somewhat disorganized set of notes in class, or based on your reading, the process of thinking through them carefully, and turning them into something concise and organized, should help your memory. In fact, it should help a lot. In general, anything that directs your mental energy toward understanding what you are learning helps you learn. I very much recommend it.
Artistry
Spending time choosing colors, writing beautiful calligraphy, drawing incredible pictures, and so on—the artistry or beautiful notes—probably won't help you learn. This is because it takes your focus off of the information you are learning and puts it on the aesthetics. The general principle is: Mental energy used toward the meaning of the information you are learning leads to learning, but mental energy directed elsewhere does not. Don't get me wrong, I think we should all try to infuse art in our everyday lives. So I recommend the artistry part too, if you are doing well in the class and have time to spare; just don't fool yourself into thinking it's an efficient way to learn.
In short, beautiful notes require organization and artistry. The process of organizing your thoughts will help you learn. The artistry part—maybe not so much.
Now if only these people would enroll in my classes, maybe my kids would stop looking over my shoulder, as I do my grading, and gleefully making fun of my students' penmanship.
