There are many Advanced Internships at DAK that involve working with animals. Because most of them require participants to be in a specific major (or small range of majors), most of them (along with many of the science-heavy AIs at Epcot) are open to Non-Alumni applicants. The listing of specific internships available will be posted at wdwcollegeprogram.com before the fall recruiting season starts.
There aren't math or science courses like at a regular college, but the classes taught at Disney are recommended for credit through the American Council on Education, and are accepted by most schools. The classes are in organizational management, hospitality management, human resource management, communications, Experiential learning, a WDWCP Practicum, and there's also a personal career development strategy course. They are taught in an actual classroom and have a set class time every week.
To enroll in a course, you basically just enroll in it after you're accepted. (Usually, you send in an interest form, and then actually enroll once you arrive in FL.)
Many participants do correspondence or internet courses while they're at WDW; this is even easier to do now that the complexes all have (or are in the process of getting) high speed internet.
