What is the best way to get your son to drink his milk?

Put it on the table. Although milk products have long been touted as a great way to "get your calcium", there are other sources of calcium as well. If junior is eating meat and green vegetables, cheese, yogurt, pudding and/or ice cream, he's probably getting adequate calcium. It's not worth arguing about. If you're still worried about his intake, give him a daily vitamin d and a calcium carbonate antacid tablet daily.