To make one gallon of root beer: One pound sugar One gallon water Two ounces root beer extract Add 1 to 2 pounds of Food Grade Dry Ice to carbonate. Tip for carbonation: put in a triple size plastic container (1/3 liquid and 2/3 air) and put the lid on tight. The pressure will dissolve more into the mix and make it fizzier. Otherwise have Club soda to add for carbonation. If you let the root beer fog too much you will loose the carbonation. Bring several pounds extra dry ice and put in as you are serving in order to let the kids see the fog affect. You must keep the root beer from freezing. Dry ice is -109.3°F and it will freeze the liquid. Add extra water if freezing starts. Do not ladle Dry Ice into cups. Put regular ice directly into cups for additional cooling. For different ideas add dry ice to grape juice and pineapple juice for a goolish witches brew.