I'm extremely shy with people I don't know well and in large groups. What I usually do is avoid situations like that when I can. I know exactly what you mean about school and having to be right. Even today, I plot out vast scenarios ahead of time when I know I'm going into an unfamiliar social setting. I plan out what I will say and do for any number of variables. That way I feel like I have some control in the situation. I think that's why I'm actually pretty confident when it comes to giving presentations and teaching - I'm in control of the situation, so I'm okay.