Look at the world from the point of view of a village of 100. A great book to help students get a sense of the world they live in and how they compare to the rest of the world population. Lessons can extend to Math and fractions, decimals, and percentages.
Kindness to our Earth is another important topic that cannot be left out when discussing kind action. Brainstorming as many ways as possible to be good stewards to our environment and Earth is a good startpoint.
Classes propose acts of kindness. Each act is put on a particular day and students make it their kindness challenge for the day. This can be combined with the kindness chain idea of adding a chain for every act of kindness performed.