All courses have accompanying materials including textbooks, workbooks, ebooks, CD-ROMs and other learning materials. The cost of materials is clearly listed on each course page. Many of the materials are included in the tuition, but a number of courses require additional offline materials that are essential to the course. Students who withdraw before the end of the year must either return all curriculum materials or pay for them. There are a very few courses in which the parent is required to purchase a textbook or workbook, and in these rare cases, that information is posted in the Course Descriptions.