Keep sick children at home for 24 hours after they no longer have fever or do not have have signs of fever, without fever-reducing drugs(acetaminophen/ibuprofen).
Do not send children to school if they are sick. Any child who is determined to be at school while being sick will be sent home.
Teach your child to wash their hands often with soap and water or an alcohol-based hand rub. You can set a good example by doing this yourself.