The irony is that the money is spent in a school where you are supposed to go for education. You would think adults would be a bit more educated about currencies. Sure, there might be some high quality counterfeits which may be challenging to identify. But wait, for the sake over 2 dollars AND to get the authorties involved
I could see why they would question the note. 1. They rarely if ever see a $2 so they might not know about $2 notes. 2. It has a red seal not a green one. 3. If they are familiar with twos, the ones they have seen probably all had the signing of the Declaration of Independence on them, this one has Monticello on it. 4. It doesn't have In God We Trust printed on it. (It is amazing how often I have heard that as being the reason an old note is considered to be a fake.) I'm surprised the detector pen didn't work on the note. They tend to use iodine to react with the starch in the sizing in wood pulp papers turning dark. The cotton/linen paper of US currency doesn't have that sizing. On the other hand the paper may have been treated differently 60 years ago. They did use a different wet printing process back then.