I thought I'd post the yummy rootbeer recipe since I got several requests. It looks so cool because the dry ice makes that fog when it hits the liquid. Kids love it. OK I love it.
Mix together 1 gallon water, 1 lb sugar, 1 oz root beer extract. (I use a large plastic container but you can use a metal container like Tif did.) Then add 1 lb dry ice. Cover with plastic wrap or the container lid. It takes about 45 minutes to make carbonation. Also, I get the root beer extract at the grocery store by the vanilla extract. Have fun and make memories with your kids.