There's no way to be prepared

Tomorrow I have a group project due; we have to facilitate a group counseling session.  We got to pick our topic and we basically made roles for our classmates to "perform" during the group. We can't however script the whole thing. So there is no way to really prepare for this.  

Our group is a support/psychoeducational group for parents of children with behavioral issues.  Wow that's a mouth full.  So tomorrow is our turn and I'm more nervous then I thought I would be.  I think the worst part about it is that after we're done, the whole class goes around and critiques us.  The.  Whole.  Class.  And let me say, that there are some people in the class that are not that good at giving constructive criticism.  Constructive being the key word.  

We're as prepared as possible, but we can't be prepared for what the group will say and how they will react to us.  And I realize that is how counseling work, but yikes!