Oh J., I'll bet you dollars to donuts that yes, your kids will have phones in high school. I'll do you one better and guess that you cave by middle school. It's just the reality of their world - if your kids want to communicate with their peers, their coaches, and sometimes even their teachers, some kind of messaging is a must. Doesn't matter if it's on a phone (which is the cheapest, simplest and most portable option) or on another device like a tablet or computer, your kids will be messaging people. Yes, high school has changed in such a way that kids do need phones, tablets, computers, twitter accounts, facebook accounts, etc. You'll believe me when your kids get there.
My two oldest are 16 and 15. My 16-year-old step-daughter was a texting fiend in 8th and 9th grade but that has dropped off dramatically. I think part of it is that the kids are all busy so they're not just sitting around texting each other like they used to. And part of it is that they've learned to not send one-word texts and actually know how to complete their thoughts before sending a message.
My 15-year-old son didn't get a phone until he was 13 and between losing phone privileges and breaking phones, he doesn't have one more often than he does. He actually uses an iPad for messaging and recently went 6 months without a phone without a problem once he got his contacts all on his tablet messenger. He also actually knows his friends phone numbers and will just call people from a land line or from my cell when needed.
It's really about setting simple rules. They don't take their phones to school, there are no phones allowed at the table, in restaurants, while visiting relatives, in church, in Sunday school, etc. There is definitely a period of high activity when kids first get phones, then the novelty wears off and they settle into using it when needed or when they're just hanging out. If we allowed our kids to bring their phones everywhere then they would of course whip them out and start texting if they're bored, but they know that we don't allow it so they leave them in the car and spend time actually talking to family and friends when visiting. If kids are glued to their phones in inappropriate places, that's a parenting issue, not a technology one.