How do you teach kindness to your children?

My son was about 2 years old when I received his first “ouch report” from school. The report said there had been an incident with my child and another boy. The two ended up with scrapes, ragged and raw, across their faces. Immediately I wondered if my son was a bully. And if he was, what then? I’ve taught him the alphabet and colors and to wash his hands before every meal. But is it possible to teach things like kindness and compassion? Can I help cultivate these skills in my child? And how important are these traits anyway? At the