Our school goes like this:

Track 1:
8th grade prealgebra, 9th grade algebra. Finishes with 12th grade precalculus or ends with Algebra 2, etc. No honors math classes are available for this track; generally kids in this track won't take (m)any honors classes, though subjects are tracked individually. However, for many kids this is acceptable and comfortable, which is fine.

Track 2:
8th grade algebra, 9th grade geometry. Finishes with 12th grade AB or BC calculus or AP stats. Honors classes available but not all the kids take them. Generally represents the "average" kid in my mind BUT there is a range of ability (some kids should really be in a different track, some just show normal variation). Most kids/parents happy with this track.

Track 3: 8th grade geometry, 9th grade Algebra 2. Finishes calculus in 11th grade with extra math class in 12th grade, like stats. This track is entirely honors. Represents advanced students; less than 2% of kids. Likely to be in all/mostly honors classes.

There are a handful of kids who are accelerated beyond this on a case by case basis. I think there's a class or so of kids tracked into something one level lower than track 1, and some kids fail classes or need remedial math at a lower level than track 1. However, track 1 is the lowest "option".
I thought track 1 was maybe 25% and 2 maybe 70%, but I think it's closer to 35% and 60%. Either way, track 1 is viewed as being below average and low-average; track 2 is average. It's a sort of gray. area. Track 3 is the advanced track.
However, the school tells everyone that the track 1 kids are "right where they should be" and track 2 kids are "advanced". Well....it helps the parents and kids feel good about themselves, but really algebra in 8th grade is the new average. Our school isn't particularly above average, either. That being said I think many kids in track 2 may benefit from track 1, even if they can scrape by.
Common core is used up through algebra and/or HS, I believe. Either that or it's just executed much better and no one notices it.

Sorry that's so long. Basically: high achievers either take geometry in 8th grade, or take algebra in 8th so they can be at the top of the class.