What Are You So Grumpy About? by Tom Lichtenheld Great book to help turn grumpiness into silliness. And as we all know grumpy and silly don't go together very well ; Bring awareness to your kids that sometimes it is best to just laugh.
Great lessons/games/activities to faciliate with children of all ages to help identify and discuss feelings. You will need to take some time to sift through them and find what works for your level of students:)