Check out these websites to journey back to the Middle Ages!
History.com's short summary on the Middle Ages, Catholic church, the rise of Islam, the Crusades, art and architecture, and economics and society. Not a whole lot of information on this website but the information that is here is good.
Professor Karen Carr, associate professor emeritus of history at Portland State University, has created a very informative site on the Middle Ages as well as other topics in history. Edited by her as well as other historians.
Annenberg Learner, a part of the Annenberg Foundation, provides teacher resources and professional development for many different subject areas. The foundation has been around since 1989 and provides support for many types of educational endeavors. Although this website may not be pretty there is quite a lot of information on the middle ages to be found here!
Alixe Bovey is a medievalist whose research focuses on illuminated manuscripts, pictorial narrative, and the relationship between myth and material culture across historical periods and geographical boundaries. Her career began at the British Library, where she was a curator of manuscripts for four years; she then moved to the School of History at the University of Kent. She is now Head of Research at The Courtauld Institute of Art. (from Alixe Bovey bio by the British Library)