Sage is the smart pick for a 2026 kids room. It is calm enough to help wind a busy child down, but Garden Sage has just enough warmth to feel cheerful rather than clinical. I would put it on all four walls and let it do the heavy lifting.
Keep the trim and ceiling in Warm White so the room stays bright, and bring in Oat Cream on built-ins, a dresser, or a small vanity for a soft layered look. Maple Brown ties it together through the floor and any wood furniture, adding a grounded, natural feel kids respond to.
The one note that makes this scheme sing is Deep Teal. Use it sparingly on a bookshelf, a bed frame, or a reading nook. It gives the eye a place to land and keeps the whole room feeling considered, not sleepy.