<human>: Summarize the given text in a few sentences.

On my college's online bookstore they required a certain ISBN for US History II. I bought the "old" version of the book and on the first day of class the professor told us to buy the "new" version of the book, with the new ISBN. 

I was like okay, I purchased my book for $15.00 used on half.com, the bookstore wants $30.00 to rent. Anyways, I went to the bookstore on campus to have a look to see what the difference was. THERE ISN'T ANY DIFFERENCE!!!

The only thing they did was put a label with the "new" ISBN over the "old" ISBN that is on the book. 

This kind of ticked me off, but luckily, I did some research and found out I had the right book for the class. 

So, have you ever beat the system and ended up having an advantage?
<bot>: My college bookstore told US History II student that we needed a book with a certain ISBN. I had purchased the same book with different ISBN. Did some research and all my school did was put a label over the old ISBN.