What is the reason for requiring students to be a junior and/or 16 years old to take certain classes in high school? I would like to take a CNA course offered, but I have to be 16 to take it, and there is also a medical anatomy and physiology class which you have to be a junior to take. I really wan to go into the medical field (I’ve had lots of my own medical problems so I know what’s all involved in much of it). Why do you ahve to be a certain age/grade to take these classes? Are there any other medical courses that I could take before I’m a junior/16 years old, I’ll be a sophmore, and I live in Utah.