Justice could mean giving wrong doers the punishment they deserve ie. the punishment fitting the crime- just desserts, an eye for an eye etc. However, it could also mean giving all people- particularly the poor and oppressed - what is right and fair for them to have ie. life, health, freedom, and dignity- this is social justice.
We have used many different bible stories to emphasize this, our main one being Jonah and the Whale which you can read below with your children in our take home sheets or watch the Youtube video.