Just out of curiousity, I wonder if she got them graded?
The notes that would be really worth more, I think are the 1937 $5 notes that are consecutive. I feel that these would fetch a premium (especially in graded condition confirming UNC+, but even in AUNC). Same with the 1937 $1 (more common, though they are) if graded 60+ she could easily put the consecutive 3 up for auction online and get upwards of $100 a piece for them.
I wouldn't mind getting a few of the $5 as the examples I have are all so-so!