Pack hand sanitizer.
According to the World Hygiene Council, the use of hand sanitizer has been shown to reduce school absenteeism by 49% by lowering the chance of germs being spread at school. Put a small bottle of Safeguard Hand Sanitizer in your children's school bag with a note reminding them when to use it. Ideally, they'll wash their hands before eating lunch or after playtime. If washing their hands isn't an option, hand sanitizer is a good backup.