Emily, one way to do this is to sign up for a Windows Live Spaces blog and send it to you site using the module. An example is here: http://fidalgoweather.net/crossings.aspx. Updating is just a matter of adding a new post. Check out Windows Live Writer, part of Windows Live Mail, for editing or creating blog entries. You don't even need to log into your account.
A second method is to use the Document Gallery. Write your news in Word, convert it to .htm format, and upload it to the Document Gallery. Then embed it on a page using an iframe.
Good luck.