Survey finds the amount students spend on course materials each year has decreased, possibly indicating students are increasingly utilizing open-source material and other educational resources. According to the survey of more than 20,000 students across 41 institutions conducted by the National Association of College Stores, students on average spent $415 on course materials in the 2018-19 academic year, down from $484 last year. Student spending has declined almost every year in the last decade -- in 2008 students spent an average of $700 on course materials.
https://www.insidehighered.com/news/2019/07/25/spending-and-costs-textbooks-continue-decrease-according-surveys