My top tip would be to try and pour the bags out in the middle of the parachute for maximum snowosity. After all the snowballs flew out of the parachute, I had the kids run and grab them so we could play again. The second time, we had a contest to see who could pick the most up and bring them to me.
Has anyone done this before? I don't think I saw this on a storytime blog, but maybe? If you posted it, let me know and I'll edit this.