These days teen girls have a lot of pressure on them. Where before girls were expected to keep their legs closed or be labeled sluts, these days they have to be on their game when it comes to knowledge about sex or be labeled a prude.
To remedy the situation most girls practice having sex with each other. That way when they actually do sleep with a boy in their class they will know how to have sex confidently. Plus, it helps the boys out too because girls like Little Laney and Little Lexie know what makes them go boom the best, and they can show the boys what feels good to them.