Rather than using a common nickname, Sheryl123, that you have used with other social media sites, establishing a more "grown up" name might be beneficial for students in the long run as they learn about Digital Citizenship and establishing a responsible online presence.
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If you find idea generation a challenge, it might be useful to use some of the random generator web sites out there.
Namethingy
http://namethingy.com/
This web page throws out suggested names every 10 seconds. Clicking the option can give you further control over the randomness of the page. Names like CubicStack or FunLunatic might not mean much, but might provide some inspiration for a generic blog that can evolve with you over the years.
SpinXO
http://www.spinxo.com/blog-names
Another site that provides you with name suggestions based on
Hipster Business Name Generator
http://www.hipsterbusiness.name/#
Even though it is generating business names, it might come up with a good name for a blog. Names like "Feather and Grass" might be a generic name to use for a blog name.
Random generators are great to use for names, writing ideas and blog post topics.
How do you generate your name?