People are naturally curious and some of them don't think before reaching to touch curly hair (or even body parts). (For the record, I think this happens to a lot of curlies and coilies who aren't mixed, too). You can let people know you feel uncomfortable. Tell them you don't want your hair touched when they see you reaching to touch it.
The other thing you mentioned - that neverending "What are you?" question - is trickier because people may keep asking you that a lot even once you're a lot older. I still get that question constantly as an adult. Constantly. If you don't feel like answering that, don't. You can walk away, remain silent or simply change the subject. Another thing I've done is, instead of answering, ask them the same question ... "What are you?" Once they've answered, change the subject.
One thing I try to remember is that this kind of attention can often be a form of flattery. I mean, the person found you interesting enough to tug on your hair, or ask you a pointed question about yourself. So try not to get too upset, if you can help it.