Sorry if this is a dumb question. My guess is they don't, for the same reason the country is referred to as "the United States is" instead of "the United States are", emphasizing national unity and whatnot, but I don't know where to confirm this.
As far as I've read, and my understanding of your question, I would say no. Each star only represents a state, with 50 stars in total, representing the 50 states in the US.
The progression of the flag throughout the history of the nation does illustrate the adding of stars to represent states added, but there's no direct correlation as to which star is which state. The design of the US flag goes through some pretty cool changes, and wasn't always just straight rows of stars.
Hope this answers your question!