Writing for a blog is a bit different than writing for a printed newspaper or a school essay. Students will be writing for a global audience so particular attention should be paid to make the content relevant and interesting. Spelling and grammar are also both very important! Check out these guidelines on how to write interesting blog post titles and content.
I suggest that you develop/write your posts in a Google Doc and then paste into Blogger. If you decide to write directly into Blogger, be sure to save your work often.
Have fun blogging!