I actually sort of did this sort of thing at that age. We called it sexing and even though there was no actual penetration, it was considered sex.

You'd give the girls some of your best comics, she'd lay on her stomach and read, and you'd sit on her buttocks and grind away. So basically to get laid, you had to have comics that kept the girls interested long enough for you to do your thing.

At parties we group sexed- since no nudity was involved, girls lay side by side reading or watching cartoons while we humped away. When we discovered we were doing it wrong the entire strategy had to be changed, and suddenly things got very complex.