Kids now exactly how to "work their parents to get what hey want! And they will do exactly that. I have a 13 y/o great kid excellent student, athlete, saught after by all of her peers. Still, she is a product of a broken and very dysfunctional home, just trying to survive. She is also a teenager. Remember they have their own intentions (just to have fun =)) Relax.
imho:
1. What happens at your house stays at your house and vice versa
2. Believe the best
3. Let the punishment fit the crime
4. Pay attention to the goal don't get side tracked with the unimportant details what is it you are trying to accomplish in otherwords pick your battles
A childs spirit can easily be broken by a few harsh words.