The only differentiation that we've seen with Connections in secondary (or primary, for that matter) is pretty blunt.
a) "special" electives-- in Literature, grades 3-8. Which is great. It was definitely a highlight for my DD, but then again, she LOVES reading, and loves analysis. Lots of discussing, sharing special (individual) projects, etc. Junior Great Books. Which I mention only because many of those same literature selections have
reappeared throughout the honors/AP high school curriculum. Yes, that's right-- apparently not only do kids at high LOG not get much in the way of authentic differentiation to meet their needs, they also (unlike the kids who aren't designated gifted) get to see things TWICE.
DD was not slow to pick up on this, by the way.
b) Math-- compacting and acceleration, but NOT self-paced. Well, okay-- sometimes, but only if they know you and you ask, and it costs them nothing because you will be doing all the work and supplying materials. And even then, it may not make it onto a transcript. Self-paced work is discouraged in secondary. Strongly discouraged.
c) secondary, all science is "leveled" as honors/GT, standard, or basic skills. No differentiation beyond that, and you MAY NOT work self-paced. Social studies is leveled in high school courses. Nothing else is, however-- not electives, not languages.
d) AP coursework exists-- kind of. That is, they have a pretty list of courses on their marketing materials, but what they don't tell you is that about 30-40% of that is actually available in YOUR state. At best.
On the other hand, they DO allow acceleration pretty readily-- but mostly that happens in primary, because in secondary, they expect students to work synchronously. The honors track in secondary is most appropriate for bright-not-quite-gifted students. You can imagine what that means for an EG/PG student, even one who has been accelerated.
Cricket's description sounds lovely. I've never heard of anyone in our state getting anything close to that.
Oh, and UM-- I do think that tracking/grouping is coming back into vogue. That is how Connections does things with their "Honors/AP" track, after all-- it's just that if that is
all that happens, it may well be inadequate, and in some ways worse than nothing at all, because administrators turn it around and tell you "Yes, but.... advanced group! Shiny!"