"Dear teenage boy at the skate park:
You're probably about 15 years-old, so I don't expect you to be very mature or for you to want a little girl on your skate ramp for that matter.
What you don't know is that my daughter has been wanting to skateboard for months. I actually had to convince her that skateboarding wasn't just for boys.

So when we walked up to the skate park and saw that it was full of teenage boys, she immediately wanted to turn around and go home.
I secretly wanted to go too because I didn't want to have to put on my mom voice and exchange words with you.

I also didn't want my daughter to feel like she had to be scared of anyone, or that she wasn't entitled to that skate park just as much as you were.
So when she said, "Mom it's full of older boys," I calmly said, "So what, they don't own the skate park."