Another reason we chose Blogger was for its spell checker. Most of our students have spelling that is standard enough that the spell checker is able to identify the word they are trying to spell. Unfortunately, the spell checker is only available when drafting posts; it is not available when composing comments, as our students' comments so clearly show.
Today I learned about Spellbound, an open source spell checker for Firefox that allows you to spell check forms such as message board posts, blog entries and other web page text boxes. I downloaded the extension and installed it. However, when I tried to use it to check a blog comment, it gave me an error message about not being able to find it's dictionary. I was unable to resolve the problem, but I suspect the cause was that I had just downloaded the newest version of Firefox (v 1.0.4) and Spellbound has not yet been updated to be compatible. We have not yet updated Firefox at school, so I'll give Spellbound a try there.