It's important to uncover the cause of bad breath in children. An illness, not just poor dental hygiene, might be responsible. A healthy mouth should have no obvious odor.
Bad breath can come from food debris lodged between teeth. Neglecting to brush the tongue can also lead to mouth odor. A buildup of foul-smelling yeast can easily form on the back of the tongue.
Foods such as garlic or onion lodged between the teeth can harbor odor. Show children how to floss, and reward them for flossing daily.
When dental hygiene is good, look for other answers. A strong sweet odor to the breath can indicate juvenile diabetes. A foul odor may indicate a hiatal hernia in the esophagus.
Use sensitivity, but discuss bad breath issues with your child. If your child has sinus problems or breathes with his mouth open, teach him to use a germ-killing mouthwash.
If your child tries various ways to alleviate bad breath, and nothing works, enlist your doctor. An exam for infected sinuses, allergies that prevent proper breathing or a stomach problem might be the root cause.
Allow your child to occasionally chew sugar-free gum or use mints. Help her become aware of the social aspects of fresh breath. Focus on creating fresh breath, versus criticizing your child for "bad breath."