When it comes to friendships many teenage kids are laboring under some big misconceptions. It is up to you as a parent to watch out for some of them and correct them so that they do not become chronic life-long beliefs that limit their options in life or ability to relate to others.
Perhaps the biggest and stupidest myth that teenagers subscribe to is that girls and boys can't be friends. Make sure your teen knows that the longest-term and most successful relationships come from men and women who are friends first. Stress that it is important to have a relationship with someone who likes and respects you before you get intimate and physical. Warn them about how easy it is to pretend that someone you are attracted to is actually your best friend.
Another thing that a teen that does not date is not cool. This is ridiculous as many teens do not date because they are concentrating on school, extra-curricular clubs or community interests. Many also do not date because of family or religious beliefs. Explain how it is important to develop your own character as well as relationships with others.
Unfortunately many teens also believe that a girl that has a lot of friends that are boys is a slut. This is the kind of profiling of young females that can be very damaging. If your child is partaking in the kind of gossip that brands a young woman as a slut then you need to correct his trend just in the name of being a good feminist.
Another thing that girls in particular believe is that if they are taken out on a date and a boy spends a lot of money on them then they have to put out. You need to tell your boys and your girls that money does not equal sexual favors. No one should be pressured or intimidated into giving sex to someone else. This is also why it is a good idea to convince your teens to do inexpensive or free things with the opposite sex like take a bike ride or got a movie matinee. This very wide-spread belief is also why you should always make sure that your teenage girl has enough money to get home, pay her own way or do what it takes to get out of situations where someone may be offering to pay her way in return for sex.