Classroom Blog!

I have been thinking about how blogging could be used in my classroom and I came up with a few ideas that I thought might be possible or that someone actually might do. The first could be a class blog for Driver Education where students posted their driver experiences such as with their parents, driving under certain weather conditions, or driving situations that occurred as they were driving and how they reacted to or avoided the situations. In health this would be a good way for students to keep a healthy eating journal or physical activity log for individual for each day or week or maybe a a whole class activity. Are these blogs possible? Or does anybody know of one of these type blogs out there?