I'm guessing you don't have kids or teach at a kindergarten? Good luck getting a five-year-old to pay attention that long!

I am not sure why you led with a graphic of crossing out a visual aid explaining gender and sex when you were going to dive into a verbal explanation that is more complicated.

A five year old explanation sounds more like this: "There are men and women. But what happens if someone looks like a man but really really really feels like a woman? Or looks like a woman and really really really feels like a man? This sometimes happens, and we try to help them be who they feel like, not what they look like."