What are the classes I'm obligated to take to become a Forensic Scientist? What's the minimal degree I need to get this career?

I hate to be the bearer of bad news but you don't want to go into a career thinking about how little you can do to get in the field. There is a lot of competition out there for most jobs, forensic science being one of them.
Depending on how far you want to go in that career, a bachelors degree may get you a nice entry level position but to move upward and onward, you may need to consider a Master's degree as well. As mentioned above, speak with your school counselor and research colleges are that are a best fit but try not to look at this as a short term investment. You will be putting in at least 4 more years of school and hard work before moving into this career.

If you're only interested in the "minimal", find something else to do. These professions require total immersion to be good and professional.