I don't think two kids who have sex together should be penalized in any way.

I think that adults should not be allowed by law to have sex with kids. Not men with girls, and not men with boys, or women with boys or women with women, and not anyone with hermaphrodites. Exceptions could be made if they have parental consent to get married, but I don't have an opinion yet about the lowest age for that to be allowed. And as I said, I don't have a strong opinion about 18 being the age without parental consent. I would need to think about it a lot more before I could form a strong opinion.