Background:
This descriptive study aims to investigate the instructional effectiveness of Open Educational Resources (OER).

Materials and methods:
It was conducted with 1196 university students who were enrolled in a general chemistry course with an experimental laboratory section. These students voluntarily used OER for their lab activities. Data were collected via a printed, 18-question survey.

Results:
Results showed that about half of the students were aware of the OER, and half of these informed students used it. Nonetheless, four advantages of the OER were determined: preparation for topic in advance, facilitating learning, time saving, and improving grades.

Conclusions:
Although OER have several advantages, only a limited number of them actively use it. Thus, it appears that students should be more informed about the system, which would ultimately pave the way for increased usage.