Today I was in an online session with Terry Freedman. I have always admired the work Terry does - he is the editor of The Amazing Web 2.0 Projects Book.
Doug, who was also in the session mentioned quadblogging. I had never heard of it before but have now investigated it and what a wonderful global tool for schools to use.
Schools register and are then put into groups of four. One of the four teachers becomes the co-ordinator for the quad. In the first week all of the people in the quad will visit the blog of one of the schools in the quad and leave comments etc. In the second week another school will be the focus and so on. Children will see a boost in traffic on their blog as well as comments - this gives the children the impetus to have their post ready and online.
Here is a video to explain quadblogging.