Critical thinking is widely considered an essential outcome of higher education, and academic librarians may have a significant role to play in its promotion. Librarians often deliver information literacy instruction to students through online learning objects, like tutorials. If librarians value critical thinking as a component of their teaching, it is important that these tools solicit critical thinking in their users. This study uses a thorough literature review to develop a set of best practices for teaching and assessing critical thinking through online learning objects. Those best practices inform a rubric that can be used to evaluate how much an information literacy online learning object is following best practices for teaching and assessing critical thinking.