LOL! The books are often written by the professors who change the books every couple years to foil used book sales. The NYTimes and the U.S. Congress are clueless.
That’s the kicker. You can’t even sell them back or sell them on ebay because they make minor changes and change the “edition” every couple years. A lot of these books are in their 8th or 9th edition, with little changed.
Occasionally, my kid has had a prof who said, get any edition of the book, so then the students can go on ebay and buy a really cheap previous edition.
San Diego State had rules in the 1980’s requiring no profit could be made if the book was required for the class and by written by the professor. Many books written by the professors had paper back version printed at the university for about one fourth the price of other books.
Bingo! The only book used in college courses that is worth the price is “Machinery's Handbook”. Contrary to the name,it isn't about machines. They are used every day on the job by everyone from engineers to carpenters. Over 2,500 pages of nothing but facts, figures, and formulas that cover everything. Even homeowners should have a copy in their library.