Is it common to double-major at Davis? Is it difficult to balance studies, extracurriculars and free time if you do so?
Define “common”. The majority of students don’t double major, if that’s what you’re asking. But there’s a sizable amount that do. I think I last saw the figure at 10-15%? But I’m not positive.
It depends entirely on what you’re double major is and how you personally are with each of those fields. I’m double majoring in computer science and linguistics, and while CS takes up a lot of time thanks to the amount of projects I have to do, linguistics takes up minimal time unless I have a paper to write or something. And linguistics is very light on its unit count while also fulfilling GE requirements that CS doesn’t cover, so I haven’t had to make serious alterations to my schedules to fit everything in.
You’ll have a certain number of unrestricted electives in any major, unless you’re in engineering; in engineering they basically plan your schedules out for you besides your GEs. When you’re doing a double major, essentially what you’re doing is using those unrestricted elective units towards another major. So unless you choose two unit-heavy majors with little to no overlap and/or you schedule your classes poorly, a double major won’t be significantly more work than a single major.
That said, if you’re an incoming freshman then it’s too early to be seriously thinking about this. Take classes in your potential majors before you plan on a double major.