How can you tell if you have a star note 2 dollar bill from 1976?

On modern U.S. currency, the serial number starts with one or two letters, followed by eight numbers, and then one more letter. On a star note, the letter at the end is replaced with a star. This means that the original bill was damaged during production, so the star note is a replacement.

Example: K60415896A compared to K60415896*