Except for the occasional glimpse of the backs of their heads emerging from the refrigerator, you might have stopped expecting to see your adolescent at all for mealtimes. Most teens are busy with friends and extracurriculars, and by this time, your family might have hit a pace of balancing work, school and social spaces that doesn't allow for a lot of time together around a table.
While your third plane child may look like they're pulling away, this is not a time to give up on the family traditions that provide reliable map points for them in their growth. Quite the opposite. Young people in the third plane need to know that they have a steady place back home to help make sense of the new experiences they're having, to remind them of their family's values as they encounter a wider social sphere, and to provide a safe place to be young while they practice being grown.
While you might not be able to maintain a regular dinner time every night, aim for at least three meals together each week. Because adolescents typically experience a change in their daily rhythms, you shouldn't expect great conversation at breakfast time. Instead, try to schedule a dinner together, at least once on the weekend and twice during the school week, when your family prepares a meal together, sits together at the same table, and cleans up the kitchen together. You might get some grumbling at first, but the rituals of mealtime matter for a community, and the contributions of each individual family member should be equal, especially with adolescents. You might turn over the recipe choice and shopping lists to your teens, then support them in preparing the meal or at least remain with them in the kitchen if they want to handle it themselves. Being together through the work of preparing and cleaning up the meal gives time for busy hands and open conversation, and can feel less head-to-head than if your child only appears for the table time alone.
Your teen will have other demands: friends, organizations, their own need (a real need, indeed!) for space and time alone. That's ok. They should explore and be supported in contributing in real ways outside of your family unit. But they also need, even on the days when they think they don't need it, the steady rudder of time with their family. Consider your family mealtimes as opportunities to connect with your teen, to listen to their perspective on the world, and to ask, again and again and again, "Tell me more about that." Regular time for eye contact and a genuine curiosity about who your child is becoming will lead you farther than most "How to Parent Your Teen" guides. Give them your attention. Demonstrate your interest in them. Listen to them as the young adults they are becoming. Welcome them home.