My DD was around 10 when we first starting to allow her to have caffeinated drinks. She's now 13 and we have never provided cola at home. She has a choice of tea (and I buy a brand that is lower in caffeine because of where it is grown and the part of the tea leaf they use), or decaf coffee. I know she sometimes chooses cola softdrink when she is out at parties (ie infrequently), and she enjoys having a decaf cappuccino (which has caffeine in) and iced coffees. So she does have it, but she understands why it's good to restrict her total caffeine consumption.