The French absolutely LOVE American Jazz. There are a ton of marching jazz arrangements out there. They would love you forever! I assume you have some in your repertoire. If not, Pepper Music has a great selection. I'm sure Hickey's in NY would too.

French music . . . try some marching band arrangements of some Berlioz. In his more hysteric moments, he wrote very stirring music and he's French! Ravel's Bolero would be fantastic.

The Faure Requiem simply wouldn't do . . .

Hope you survive. I had a friend with a HS marching band and he loved these trips with the kids. You are very brave . . . so was he!

Seriously, any jazz would be great, especially after the New Orleans hurricane. They would just love it.