Centers for Disease Control and Prevention is an informational site for current health issues and topics.
National Institutes of Health from the U.S. Department of Health and Human Services has information on a variety of health topics.
KidsHealth from Nemours has a section for parents, kids and teens.
Nutrition and Exercise
Choose My Plate from the U. S. Department of Agriculture provides practical information for building healthier diets.
Asthma and Allergies
Mediline Plus from the National Institutes of Health and produced by the U. S. National Library of Medicine – Information on diabetes in children and teens
Food allergies for parents – Nemours Kidshealth