Four to six exchanges should be enough. Some technical problems can arise unexpectedly when you are actually in the computer room, for example, access to the internet might be denied. This could have disastrous consequences if you have not planned something else to do. One tip is always to have some CD-ROMs at hand for an alternative activity. Encarta is ideal because students can always do research about the history or customs., etc., of the country of the students they are writing to .
Some students simply write slower or more than others.
Allow time for these students. Ensure that students save their work and copy it to both yourself and to the teacher in the other country. This prevents loss of their work and allows you to monitor what they are writing. It is best not to let students write their own individual e-mails. Two or three students should share a computer and write a joint e-mail.