Get kids to understand that you don;t get praise for doing stuff that easy but hard. Jesus ask us to do things that are hard but with his help we can do it.

Explain that when people are nasty the cycle can be broken by show kindness and love. but make clear that this does not mean that they should let people get away with doing bad things.

Have some sweets, start with a big pile and ask them if easy to share. Share the sweets out, then make a small pile (less 1 the number of people in room). ask if it easy. The end is that when they go back to church they will give away all the sweets. At the end of mass priest gives them more sweets than they gives away reinforcing the idea that the bible reading we get rewarded for doing what jesus ask us