You should.

You are their role model.

If you don't wear a helmet, you're telling them that wearing a helmet isn't important.

Okay now I'll get down off my soapbox and tell you how much I LOVED this piece.

Other than that line about the helmet

Okay, so maybe I'm still kind of on my soapbox.

But you're a really good writer! I like the way your brain works. I hate the thought of your putting it at risk by not wearing a helmet.

Okay, I'll be quiet now.