Not in domestic gross.
Avatar - 774m
EPI - 718m
EP2 - 425m
EP3 - 472m
And, as a domestic franchise, it was blown away by the original trilogy.
EPIV - 1.4b (yes, billion)
EPV - 781m
EPVI - 748m
Worldwide gross, it blows them away though.
Avatar - 2.8b
EPI - 1b
EP2 - 649m
EP3 - 850m
But, again, the franchise as a whole made more than Avatar. Though, this may not be the case after the next movie and if the third movie is released. It will be interesting to watch (even if the movies are not).
One thing I will add is, going off box office numbers alone, Avatar is hands down the worldwide unadjusted box office king. But, if you included licensing and toy franchises, I think you'll find that the prequels and Star Wars as a whole has greater cultural impact and certainly has made far more than Avatar. Avatar was a cultural blip where 3D and CGI advances merged together to create a story with a fantastic and unique backdrop.
But, not a very memorable one, and one with an extremely shallow story and characters.