This is an interesting question in that it can take in a wide selection of many classes. It is important to know that when you study Art it is a widespread subject and one that can give you skills for which can lead you to a good career. Here are some suggestions:
1. Classes to possible take for an Art Major are: Ceramics, drawing, drafting, along with Math; Algebra 1 & 2, Geometry, and Trigonometry. Also, if you were thinking of Computer graphics then that might be a choice to learn the graphics area on the computer.
2. The learning skills that you will get from taking some of these classes are: Project Development & Hands on development (Painting and Clay work, paper projects, glass staining and ceramics and Metal art work. You can also receive a lot of Pride from exhibitions or art displays within the High School events or local events, and if good enough can receive ribbons, or medals or certifications. These particular awards can be stated on your resume or application for college.
4. The benefits for taking Art Class are many: The learning of concentration; Attention to detail, Improvement of hand/eye coordination, Creativity, and Thinking outside the box, and Follow thru on a project to the end. Problem solving and social skills will be upgraded for you and good experience to carry you into a career.
5. If you do take this advice I would like to add another suggestion; that being keep a portfolio of the projects that you have done. In other words take pictures of your art exhibits and projects so that you have evidence to bring with you either for a job or for your counselor at school. If you decide on graphic arts print out your graphics to also put in your portfolio. You will have something to show for what you have done, and others may not have put together a portfolio. This will make you look better than the rest especially if the art is good.
I hope this helps but when you get to college please make sure that you get a counselor that is aware of your Artistic skills and helps you to make the right choices for your major.