Or at least that's what I thought about I got to the part about the guilt the author felt over the purchase, and the teacher trying to buy them out of pocket. It really is despicable that we require 100$+ purchase every student's education when there are so many realistic cheaper alternatives
This could be solved with a simple sellback program.
1. Purchase from school for $100
2. Sell back for $95
3. Repeat forever until calculator breaks