One consequence of a more student centered approach is we give more responsibility for sequence to the individual, yet still have a list of vital topics we want covered, or at least visited. This suggests a "theme park" metaphor where the rides are clearly labeled and described, with suggested segues between them, but with few stipulations regarding a "one right order" (though you may have seen in the gym, where they hand out "scenarios" or "storyboards" with possible workouts -- abs intensive, leg focused etc.).
For example, Pascal's Triangle is a grand central station, as I've many times mentioned, but some kids are coming from a polyhedral numbers angle, finding familiar sequences like triangular and tetrahedral numbers, whereas others are in the midst of binomial theorem applications, looking at rows as coefficients in some polynomial expansion of (a + b)**n. We have teachers or guides at each exhibit, understanding of where a student might be coming from, and with advice on where to go next, but having a map in hand is sometimes most what one needs.
Probably states with the more advanced boards of advisers have already picked up on this networked approach, is it traces back to "mind maps" which many schools have been teaching for some decades now. Small wonder then, that as graduates of these programs would reach adulthood and assume responsibility, that the math curriculum itself should come to resemble a "mind map" in many ways.
Of course we still have the older, more traditional concepts of "spiral" and "outline", the latter more of a tree, i.e. a traditional sequence. Sometimes we just need to use scissors to slice tables of contents apart, glue them to construction paper, use color coded yarn to show possible pathways. That's a primitive approach, more suitable to workshops than published writings on the subject, but it gives the idea. 3x5 cards also useful.
PS: if this "theme park" approach seems reminiscent of Lou Talman's postings to this archive, that's probably no coincidence.