I have been learning French on my own for the past two years, and am always looking for reasonably priced and interesting resources. This CD of stories fits the bill for me perfectly. The stories by Goscinny are brilliant and funny, written in quite colloquial French: everything is "chouette" and "terrible" (which for Nicolas means "awesome"). The author, Goscinny, was also the author of the Asterix comics.
The audiobooks are very well read by Brigitte Lecordier. She puts on funny voices for the different characters, and conveys all the excitement of a child telling a story. The reading speed is a bit fast for me, but it fits the narrative tone very well.
Here's how I am using these CDs for my French studies: The French of Le Petit Nicolas is a bit above my level, but the humour in the stories is keeping me interested. I first listened to the CDs carefully while going for walks. On the first listening I was just managing to get the gist of what was happening, but that is an important skill to develop. And even when I was understanding half (or less) of the text, some passages made me burst out laughing!
After listening to the CDs twice, I began to read the books. I recommend the kindle version, because you can install a French dictionary on your kindle for the auto-lookup. While reading I try not to look up every unknown word, but only when a word is essential to understand a sentence. I'm on my third reading of the book, and have listened to the CDs 6 or 7 times. With each reading/listening, more and more of it makes sense, and I have been having fun every time!
I only wish Brigitte Lecordier had done the reading for the other audiobooks of Le Petit Nicolas available, since the others are not as good (according to reviews on Amazon.fr).