Gretna Heritage festival across the river. We ended up liking it so much we went back the next day! What a great event for children. Adults were $15 at the gate, kids were free. Large selection of food of course, and a minimum of five stages with live music ranging from cajun to classic rock. Plenty of room to dance, which my children love to do. We manage a combination of swing and ring-around-the-rosie that can clear the dance floor.
Our favorite area was the festival's version of Little Italy. Non-stop "mob hits" and the largest oysters I have ever seen - what's not to love? And as an added bonus the Mardi Gras Indians paraded through. Just to remind everyone that we were not, in fact, in Italy.
Our second favorite area was the levee. A stage on either side provided musical backdrop to my children's death-defying slides down to the bottom on squares of cardboard left by other slightly more enterprizing kids (until they found the cardboard they had to make do with simply rolling down the levee. Always a classic but less of a thrill than the cardboard box toboggan). The levee almost made the amusement park midway rides slightly less exciting. Almost.