Mustard is having a real moment in kids rooms right now, and it is easy to see why. Golden Mustard on the walls feels like sunshine you can keep all year, warm and happy without tipping into baby-bright primary colors. It grows with a child, too, so you are not repainting in two years.
To keep all that warmth from taking over, I lean on Cloud White for the trim and ceiling and a gentle Soft Greige for any cabinets, a dresser, or a built-in. Those two quiet colors give your eyes somewhere to rest. A Honey Oak floor or wood furniture picks up the gold and makes the whole room feel cozy and grounded.
The piece that pulls it all together is Deep Teal. Used in small spots — think a chair, a rug, or a row of pegs by the door — it cools things down and makes the mustard pop even more. Start with mustard as your main color, let the neutrals do the calm work, and save the teal for the fun details.