'Factfiles' are a sub-series of 'Bookworms' with a non-fiction angle providing factual information for students on a wide variety of themes. Exercises at the back of each book check students' understanding of the text and provide ideas for activities and project work. Oxford Bookworms enjoy a world-wide reputation for high-quality storytelling and a great reading experience. Research shows reading a lot improves all your language skills. Experts recognize Oxford Bookworms as the most consistent series in terms of language control, length, and quality of story - very important for fluent reading and extensive reading. There's a wide choice of titles too - something for everyone.