I, personally, find myself more comfortable around girls - this is probably a result of the incompatability of my personality & the guys at my school’s personality - when in smaller groups. But guys are much easier for me to talk to, as their “small talk” tends towards lighter & more interesting topics. Girls seem to stay in 2 regions: 1, shallow and meaningless; 2, personal and serious. I do well in neither of those. But as I said, at school I am more used to the day-by-day company of girls so it’s easier for me to relax and know how to “behave”.