This is an activity for a very good intermediate or an advanced group of students.
First, establish six vocabulary categories, say: animals, furniture, means of transport, technology, science and geography. Then decide on the name of a personality, preferably French-speaking.
For each category do a brainstorming session with the whole group, or get students to do it in pairs if they are keen enough. Write down on the board all the words you can come up with. This shoud take at least ten minutes.
Next, get the group to pick one word from each category.
Now it's story time. Together with the group, or, once again in pairs or groups, the class has to produce a fantasy story of six complex sentences, with each chosen word featuring once in each sentence. Stress to the class that the aim is NOT to get every word into one sentence.
If done in pairs or groups you can then listen to each story. You may prefer to do the task all together as some groups may lack the imagination to produce good stories on their own.
The whole task should take around 30 minutes, including 10 minutes for vocab brainstorming. By the end the class will have revised or learned vocabulary, practised listening and speaking and improved their grammar.