With 6-9 year olds, I would rather do some art project. Here is an idea, maybe it would work for you.
Assign them to paint a picture using only the 'pure' colors, no mixing allowed.
So purple is not allowed, because that is blue and red. You can show them, how it would be mixed,
Gray is not allowed, because that is white and black,
and so on.
You end up just with the primary colors + white + black.
Now ask them to paint different things (i.e. in groups). One group paints a meadow, another a street with houses, another group a bunch of people.
They will have difficulty doing so, and will probably long for the colors that are mixed. They may also notice that their pictures come to be very stark looking. Maybe some girls will comment that all the girly colors are gone.
Then discuss: Why is it so difficult to paint a meadow with only primary colors? Well, because the world we live in, does not only contain primary colors. It is rich and full of life, because we allow all colors of the rainbow and need all colors of the rainbow. And we need both the softer as well as the darker hues.
Then end the class and let them make a new version of their picture with all colors allowed. Most kids will love the new gained freedom.
No translation to any abstract or sociological concepts needed. We did not learn all this at age 8, neither will they.
But if you develop in them the longing for all colors of the rainbow and a question of, who makes these rules anyways...you have achieved everything you could hope to.
And don't despair that the kids naturally parrot what they have been taught, we all did that at that age. And in Russia as well as probably many former Soviet regions, the top down rule book on masculinity is a strict and macho one.
By the way, I think you are more than brave to bring Adam, as an artist, to these kids. You were probably not expecting so much controversy, but in reality, Adam is in most Soviet places, as well as seemingly in certain parts of the US, more than just controversial, he is still the outlaw.
But all that is a more mature conversation, you are teaching kids, and creating learning experiences, not theoretical discussion, especially in a foreign language on top of it. And no, I would not bring that art class back around to Adam. They are too young to connect those dots. I would just let the learning experience linger.
Hope this helps.