Thanks for the replies.
It looks like I'll have to set up an IMAP server and export out the .dbx files to .eml, then import them into the IMAP server, then import them into Live@EDU. Apparently the systems that Live@EDU understands are Exchange 2007/10, Exchange 2003 or IMAP server, at present we have none of these. You'd have thought MS would support their own software?
James, Changing to office365 won't as far as I can tell help me get the Outlook Express files directly into the cloud. And looking at the required specification for Office365 our PCs will struggle!
Thanks again for your help. I'll keep looking for an elegant solution.