In fall 2013, the Student Public Interest Research Groups conducted a survey of 2,039 students from more than 150 different university campuses. Key findings include:

65% of students said that they had decided against buying a textbook because it was too expensive.
94% of students who had foregone purchasing a textbook were concerned that doing so would hurt their grade in a course.
Nearly half of all students surveyed said that the cost of textbooks impacted how many/which classes they took each semester.
82% of students felt they would do significantly better in a course if the textbook was available free online and buying a hard copy was optional.

Open textbooks are a solution to these academic and financial concerns.

Fixing the Broken Textbooks Market: How Students Respond to High Textbook Costs and Demand Alternatives by Ethan Senack, The Student PIRGS (CC BY)

Student and Faculty Benefits

Open textbooks address not only financial issues, but pedagogical ones as well. The open licenses allow for updates, edits and other changes to reflect the latest research and developments. Faculty may also choose to involve their students in the production or review of the content.

Faculty authors have their own process for writing and publishing an open textbook, depending on their research and writing methods, as well as the resources available at their institution. Watch open textbook faculty author Linda Bruslind from Oregon State University talk about her process in this 1-minute video.

Perceptions Research

The Review Project, led by John Hilton III, provides a summary of all known empirical research on the impacts of Open Educational Resources (OER) adoption. Here's the summary as of July 2018:

Several thousand students and faculty members have shared their perceptions across more than a dozen studies that have focused on perceptions of OER. In no instance did a majority of students or teachers report that the OER were of inferior quality. Across multiple studies in various settings, students consistently reported that they faced financial difficulties and that OER provided a financial benefit to them. A general finding seems to be that roughly half of teachers and students find OER to be comparable to traditional resources, a sizeable minority believe they are superior, and a smaller minority find them inferior. -- https://openedgroup.org/review

Read the latest at The Open Education Group, or watch this 5 minute recap from 2016:

"A Review of the Effectiveness & Perceptions of Open Educational Resources As Compared to Textbooks" by Research Shorts on YouTube (CC BY)