Got some interest in the French language? Start blogging about learning the French language. Learning a new language, especially one as beautiful and useful as French, is a popular interest. In fact, the only other language I would have suggested is Spanish! A lot of people worldwide are enrolling in French lessons and aim to be proficient in French.
You can use your own experience and resources, or collaborate with French language teachers, linguists, or some native French speakers to effectively run this blog. Though this blog would be about learning the French language, you can expand this to include different language courses, travel tips for France/Paris, and blogging about French culture and lifestyle.
Blog Name Idea: FrenchOn.com