Seminars have started in several Missouri cities, teaching store clerks how to avoid selling cigarettes to minors. The red cards with the white letters reading “We Card” are seen on hundreds of stores throughout Missouri -warnings that the store wants to see some identification if the clerk suggests a potential cigarette purchaser is not yet 18. The Missouri Retailers Association says people should be checked unless they obviously are older than 18. Seminars are being held in 13 cities in the next week to train clerks to watch out for fake I.D. cards and even more creative ways to fool clerks. The Mid-America Grocers Association thinks it’s clear the campaign is working. It believes one of the most valuable tools in the campaign is the calendar kept near the cash register – saying a person can’t buy tobacco if he or she was born after that day’s date.