The present study aimed at developing and evaluating a five-week online course to teach critical thinking skills in reading to foundation programme students in Arab Open University- Oman Branch. The study attempted to answer the following research questions: 1. What are the steps used in designing an online course to teach critical thinking skills through reading to foundation students? 2. How can students' learning in the online course be evaluated? 3. How can the online course be evaluated? Nation and Mcalister's (2010) language curriculum design model was used to design the online course. The course was implemented with 11 students from level two of the foundation programme. After its implementation, the course was evaluated by the participating students, the course instructor and three course reviewers using three different research instruments: end-of-course evaluation form, a semi-structured interview, and a course evaluation rubric. Students' results in the course assessment indicated an average achievement of the course learning objectives. When surveyed at the end of the course, students had an average to a high level of satisfaction about the course design. The course instructor was satisfied with some course design elements and was not satisfied with student-to-student interaction in the course. She identified some areas for further course improvement. Similarly, the course reviewers reported a good satisfaction level with elements of the course. However, they also indicated an issue with students' interaction in the course. They suggested some modifications to some parts of the course, and they suggested adding some materials to the course. Various modifications were recommended to enhance the online course. Implications of the study are discussed, and recommendations for further research are suggested.