I’m a freshman in high school and I’m interested in majoring in two areas that are even in completely different departments. One is in the art department, which is animation, and the other one is animal behavior, which is a science department. I’m not even sure what to pick for next year’s elective. I’m equally passionate in both interests. I’ve always been the scientific artist/artistic scientist and a jack of all trades. I haven’t found any colleges suiting both of my interests, and if there is, I’m still uneasy of double-majoring. I don’t want to potentially ruin my social life (I barely have one in high school. I’m hopping to change that by the end of college.) by being crammed up in my dorm all day. I’m still human; I need time to relax. I’m not sure what to do. I’ve been interested in animal behavior since 3rd grade and it has stuck with me ever since. I’m still just as passionate compared to myself just discovering animal behavior. Animation was the one thing I was longing for since 3rd grade as well. Using simple pictures to tell a creative story was something I wanted. I’m not the best in realistic art and writing has never been my strong side (not because of the creativity part. It was always the fact that it was harder for me to convey my thoughts to words, and my vocabulary isn’t the best either.) but I’m good at storytelling and love drawing. I’ve never discovered animation until 8th grade, but animation just seemed right when I first saw that there was opportunity. I’m not sure what to choose, both feel like potential jobs in the far future, but I know I’ll have to leave one behind as a hobby/interest. Maybe double majors aren’t that bad, who knows? If anyone can give out some suggested colleges, tips, and advice, then thank you. 
It’s an extremely selective school, obviously, but Penn was designed for people with multiple “clashing” interests in mind (I mean, it was founded by a Postmaster General/printer/scientist Ben Franklin). I’m doubling in Biological Basis of Behavior and English, and I have friends who are doubling in political science/chemistry and biochemistry/fine arts.
I think focusing in on the animal behavior aspect in your college search will yield better results than animation, as that’s the more specialized field of the two. Columbia has Neuroscience and Behavior. Emory has Neuroscience and Behavioral Biology. UW-Madison has a good zoology program. Minnesota has an “Ecology, Evolution, and Behavior” major, but their college setup would make it difficult to double. Ditto the animal science major at Cornell. Bucknell and Texas A&M have degrees specifically in animal behavior. (I’m pulling most of these from my own college research from a few years ago.)
As for advice, I don’t think double majoring is the hardest thing in the world. You’ll likely be taking the same number of classes as everyone else, they’ll just be centered around things you really enjoy. Most of the time, the increased major courseload will come at the expense of electives, so it’s more deciding “do I want to go deeply into two things, or deeply into one and broadly into another?” For me, the double makes sense and is a lot less taxing mentally and physically. I’m more productive when I can change gears. This weekend, for example, I read 150 pages of Jane Eyre for my literature class between doing my calc problem set and bio notes.
For what it’s worth, you don’t necessarily have to leave one thing behind, either. Greg Graffin, Dexter Holland, and Milo Aukerman are all touring punk rockers with Ph.Ds in the sciences, and both Graffin and Aukerman have taught or done research while actively making music (Holland hasn’t had much of a chance, as he only got his doctorate this past spring).
You’re still super young and will have several years to change your mind, but I think you’ll be happier embracing both interests rather than try to choose one now.
If you like both, then you could look for dual degree programs, or ones that allow you to make your own. There’s a girl at my school (Drexel) who made her own major called “Digital Storytelling” which might fit what you want.
For HS, I would take courses oriented towards science (but make sure to take Bio, Chem, Physics and not just any courses with animal in the name). Take challenging english courses…you will need be able to communicate your thoughts. Take drawing related art classes as electives. Maybe work your way to AP Art so you can develop a portfolio.