R.M.
My mom would freeze milk before a trip and we'd use it as the ice in the cooler for the first day and then shake it up and drink it while it still had some ice crystals in it -yum! If we were traveling without a cooler any fresh milk in the fridge went into the freezer so we'd have milk at home when we got back.
As to Victoria's note about when to switch to skim - I have to disagree. As an older mom I did quick search of reliable websites to see if things had changed in the last couple of years. Developmental specialist and Drs. still suggest that the only reason to switch to a lower fat milk before age 2 is when a baby is obese. Babies really need the fat for proper brain development, calorie intake and proper absorption of fat-soluble vitamins. "Whole" fat milk still only has 4% fat.