Discuss with the preschool teacher what the recommended amount of time is for hanging out on the first day of preschool . . . and stick to it. If 10 minutes is OK, then watch the clock — and your tot — and then say goodbye. Showing your child that you feel confident about leaving her at school let's her know it is a safe place to be. It may seem like a good idea to sneak out if she's having fun, but it's best to give a quick goodbye hug and a peck on the cheek before heading out.
Source: Flickr user sparklecandace