I would like to invent a toothpaste that is flavorable yet cleans your teeth. The deal is this toothpaste will turn a kids teeth brown if he/she smokes a cigarrette, turns green if he/she smokes marajuana, and turns bright yellow if he/she drinks. This would embarrass a teen so much that he/she would not think about doing any of those mentioned above again. The teen wouldn't know what made his/her teeth turn the colors and the only way to get the original color back was to brush his/her...