In order to qualify for a license, a gym teacher must have a minimum of a bachelor's degree and pass competency examinations covering both general education and topics pertaining to their area of specialty. After a teacher is licensed, they must also meet continuing education requirements set by their state.
Mistake #3: Keeping mixed formula out too long. Formula that is sitting out at room temperature must be thrown away after 1 hour. If it is in the refrigerator, pre-mixed formula (also called ready-to-feed formula) that is opened must be thrown out after 48 hours. Formula that you mixed must be thrown out after 24 hours. Mistake #4: Re-using leftover formula.
Even properly refrigerated liquid formula should be used within 48 hours; if you've made a batch from powdered formula, you should use it within 24 hours. Remaining powdered formula should be used within a month after opening. Any formula left in the bottle an hour after your baby has started feeding should be discarded, so try not to fill the bottle with more than he usually takes. And as with any food, particularly one meant for a baby: When in doubt, throw it out. Contributing editor Heidi Murkoff is the coauthor of the bestselling What to Expect When You're Expecting (Workman) and the author of the What to Expect Kids series of children's books (HarperCollins).