Since milk is mostly water, its boiling point will be close to that of water, which is around 100 degrees C (the exact number depends on atmospheric pressure). In the same way, the exact boiling point of a cup of milk will depend on a lot of things, such as what type of milk it is, how much fat it contains, what altitude you’re at, etc. Mixing salt or sugar (or other solutes) with water will raise its boiling point slightly, and a good guess for milk is that the boiling point will be a fraction of a degree C higher than that of pure water at the same atmospheric pressure. For information on some of these factors, look here. You may be interested to know that there is a special process in which milk is brought to a temperature just below its boiling point, then cooled down again. This is refered to as "scalding" and is commonly used for making yogurt, cheeses, ice creams, and other products. To find out the exact boiling point of a glass of milk, try boiling it yourself. Measure the temperature of the milk with a thermometer just after it reaches a boil (if you wait too long the temperature will increase beyond the boiling point, as the gaseous milk begins to heat up). But you should be aware that the milk probably won’t taste quite the same after boiling it, so don’t boil anything that you really want to drink! ;) http://van.physics.uiuc.edu/qa/listing.php?id=1451