Researchers increasingly embrace online courses to compensate for lack of access to educational opportunities otherwise available in traditional school settings. Researchers also recommend alternatives to traditional AP coursework to better meet the diverse learning styles and needs of advanced learners. These recommendations have particular applicability to students attending poor or rural schools where access to advanced course options and gifted programs are limited, to students who cannot ft additional advanced courses into their school schedules, or to homeschooled or homebound learners. However, little research exists on the use of online alternatives to traditional AP programs for students who lack access to advanced course options. This qualitative study investigated the learning outcomes for 138 students enrolled in an advanced online case-based course in environmental sciences. The course utilized problem-based and case-based learning methods and was developed using the guidelines provided by best practices for advanced learners and science pedagogy. Analyses of student online discussion boards, case resolutions, student grades, student and parent surveys obtained at the end of the course, e-mails, and AP examination results showed that many students enrolled in the course demonstrated learning, engagement, and challenge. Findings further support the conclusion that the course provided a viable learning alternative to traditional AP environmental science courses for many, but not all, students. (Contains 2 tables.)