"Do you know who this is, or when this picture is from?"
"No."
"That's okay. What CAN you observe about it?""She has a white dress/a hat with a feather/an interesting haircut... I'd guess she's about 3 or 4 years old... It must be an old picture, not just because it's in black and white but because she's not smiling and usually today photographers get kids to smile for pictures..."
"Great! Yes, this picture is probably from 1884, so the person was about 2 years old. This was one of our country's former presidents: Franklin Delano Roosevelt. See? Here he is all grown up."
"...waaaaaat."
"Do you have a question?"
"Why was he in a dress?!"
So we learned the history of a few cultural norms, including the tradition of dressing boys and girls in white dresses until about age 6 basically just because white was bleachable/thought to be a "kid" color, and how pink and blue emerged (and eventually swapped) as color "codes" around the WWII era.
We looked at the pictures from the Lumberjanes series and noticed how different all the girls look - their body types and hairstyles and fashion choices, quite different from what we're used to seeing in, say, Disney movies.
We talked about frustrations we feel when we're shopping for new clothes and it feels like a lot of choices have already been decided for us.
We learned what "inclusive language" means (they knew the phrase from around the church, but not what it meant). We recalled the Doxology we sing and how in this church instead of "Father and Son" we say "Creator and Christ." (Later on, the kids silenced our activity room just to be able to listen for these words during the service.)
We studied several feminine images for God used throughout the Bible, and talked about the kids' perception (one they brought up) that girls are encouraged to look up to men and sometimes to emulate traits considered masculine, and boys are comparably less encouraged or actively discouraged from looking up to women and emulating traits considered feminine.
We read an article from a mother talking about her 5-year-old son, who agrees vehemently he's a boy and also loves painting his nails and wearing dresses. We learned from this mom that some of the best ways to love people are to listen to them, to use the pronouns and names they ask us to use for them, and not to assign them a label based only on our perceptions of them. (I revised an excerpt from the full text at this link; I removed some major portions and some otherwise significant terms for both time and clarity suited for where they're at right now.)
We learned that sometimes it's good for kids to learn cultural lessons from adults about "how things work" and "why things are," but they should also trust their inner sense of who they are.
And then we spent the rest of the time making fashionable people cutouts to adorn the bulletin board beside the Pride flag. The signs we'll post with them read: "God is gender fluid" with a definition below it, and: "WE ARE ALL MADE IN GOD'S IMAGE."
This is one of the ways I followed up with the kids who asked me about a month ago, 'Why can't boys wear dresses?' Question-led lessons are my favorite lessons.
If you are also an educator/caregiver and any part of this lesson plan would be helpful to you, you are welcome and encouraged to use it.