I'd recommend hip, wrist, knee, elbow, and helmet. Definitely some shin guards if you're going to do some rails. It's a different mentality once you're older compared to those unique years as a youth when the parents provided for almost everything. I have to minimize the possibility of injury not only to keep enjoying the rest of the season, but to make sure I'm fit to work to pay my bills as well as avoiding out of pocket medical costs.
For new people that have some advance notice on their trip I seriously recommend getting pads before your first day out. You will fall, and it will hurt at times even with pads. It will be so, so, so much worse without them. Take it from a guy who used no pads at all when learning. Sprained wrist 3 times in a row. Elbows and knees were purple and the ass was in terrible shape. You will still be sore (feels like a max lift workout at the gym to all parts of your body), but you'll have saved yourself some lasting pain and have confidence to advance to better boarding.