Thinking back on my HS days, I'd say that was generally true.
The cheerleader girls stuck together, the band girls stuck together, and the eggheads stuck together. But some were both cheerleaders and egg heads; so you'd see them in both groups. And some were band members and eggheads; so they'd populate both groups.
Anyway, the really hot girls were in the cheerleader group. And the plain ones were in the egghead group. The band group had a bit of both. There were exceptions, there always are with humans.
The guys did the same thing. They formed jocks, band, and eggheads groups and hung around with their own kind.
We didn't have what you call relationships back then. We dated, but not in a serious way...again there were exceptions. But generally speaking the cheerleaders dated the jocks, the band members dated band members, and the eggheads dated each other.
For your reference, I graduated from HS in 1954.