The site took me approximatelly forty-five minutes to review the materials. The lessions are illustrated very remarkable by interesting arts and graphics which hepl the lessons more understanding and allurring. The materials were written clear ,well explaination, and reliable. The structure of the site is simple and organized, so it is easy to access. On the Paul Kunkel's home page lists alot of useful mathematics links. The Kunkel's mathematics lessions are very effective for eduacational purpose.