This is your first day of school my baby and I know it will be a bit scary without your mommy and daddy, but you will be safe and there is nothing to worry about and you'll be home soon. 
Every day from now on there'll be new things to learn and things to deal with, but you'll make new friends, although sometimes someone may not be nice to you, not all children are as good and as kind as you are. 
It will be this way throughout your life, people coming into your life, not all of them nice.
But try not to be angry with them as something has made them that way, so they don't know any better, but they will never find happiness until they learn a better way, so try to show understanding if you can.
Maybe they will learn from you. 
Just remember, your mommy and daddy love you very much.