Do you already have a Star Note in better condition than that one? If you do, then spend them all. If you don't, then save the * until you get another, better one. Always be trying to improve your collection, remember, condition trumps almost everything. Do you see the green seal on the words ONE and TWO ? Look for other colors such as red, blue, yellow, brown, etc.. Color is the easiest thing to spot when you're in a hurry. You can't always take time to closely examine every bill that may cross your palm. Lego, you've been around for a while. Is there something about the bills that makes you ask about them? I looked again and noticed that on the second bill you posted, the seal is slightly offset to the left. I doubt if it's enough to matter value-wise.
I just wanted to clarify. I had them in a book, and forgot why I laid these notes aside about half a year ago.
Looks like an old steel paper clip made that stain on the 1956 year note. I would keep the star note and spend the rest. Unless you know someone born in 1956.
I would keep any star note because Ive never gotten one. I did get a $20 out of an ATM that was a star note but didnt take a close look or care because I needed gas and spent it immediately. I regret not at least taking a picture of it to research for fun!