Frankly, I believe that when teaching the commandments or any other aspect of our faith to anyone (including children) our best source is always the Catechism of the Catholic Church.
Based on what the CCC says (2331 and following), I think that the following are the most important messages to pass to children regarding the 6th commandment:
- Duties regarding their sexual identity
- What God wants for maried people
Personally, when teaching the 10 commandments I insist in the fact that commandments are given by God because he loves us, as a way to protect us from getting hurt. He knows that we don’t necessarily know what is good or bad for us (we are all His children). On that same positive note, I encourage children to think on what to do to comply with each commandment, rather than what **not **to do.
So, in the context of modern times in North America, I would propose the following to the children, as ways to comply with God’s 6th commandment:
I understand that God created us boys or girls, with different qualities, but He loves all of us the same way, so I feel happy and proud about His choice for me.
I respect my body and that of others, because God lives there.
I don’t think or do impure acts.
I know that a marriage is when God unites forever a man and a woman to love each other, as well as to receive and love their children if He sends babies to them.
So for the 3rd point, the natural question I would expect is: “What is an impure act?”. I believe that for most kids it should be enough to explain that if there is something you feel you need to hide from Mom and Dad, most likely you should not be doing it. Most likely, it is an impure act.
Depending on the ages, culture and what you have discussed with the parents and priest, the other points open the discussion to talk about how some people sometimes don’t like that God chose for them to be a boy or a girl, how some people gets confused and think that a marriage can be done between two people of the same sex, how it is important that people dress properly, divorce, etc.
Just my opinion. Always consult your priest.
God bless you.