This is the age (13-15) when some parents choose to give purity rings to their daughters and sons. Websites with information you might find helpful are: http://www.christianliferesources.com/?library/view.php&articleid=313
I absolutely love the idea (where possible) of a same sex get away with time to cover material in the book together (Moms and Daughters, Fathers and Sons.) There is absolutely no substitute for you pouring your family's values into your own child. It might seem like they are not listening but just keep trudging ahead. Then give them the gender appropriate book with your own message written inside and they can continue to use the book as a resource during their teen years. You'll have many opportunities to remind them of how to respect, care for, and protect the opposite sex as they connect with first boyfriends or girlfriends or attend school and outside events.
You might say things like
- God's plan really is for our sexuality to be expressed at its best within a lifelong committed relationship - marriage.
- The physical relationship you have with someone should to be in-line with your spiritual and emotional relationship.
- My hope is that you take time to get to know the whole person as you look for a person to love for a lifetime. It can't be a bad thing can it to develop a really great emotional friendship with someone and to learn about one another's belief systems before you let the physical side of things go to far down the path."
- I trust you to make good decisions and to be protective of yourself and others.