My experience is that AA has been pretty aggressive on JFK-CDG pricing in the spring and fall, but perhaps not as much (or, at least for as many weeks in advance) during the summer. (e.g. I was able to snag a $360 R/T on AA 44/45 in economy - purchased last November, flew March/April.) I've definitely seen well priced AA fares marketed since then, but the windows have been narrower than the one I took advantage of.

So I'd watch like a hawk right now if you're looking to fly in August. That said, they may have capacity to fill, as a second flight has been added (albeit on a 757) on M-W-F-Sa through 8/21.

Would echo poster before me to consider OpenSkies if you don't mind going into ORY on 757 instead of CDG. Same mile earning table as mainline BA.