As students are walking in I have this projected onto the whiteboard (I project right onto the whiteboard so I can draw on it):
They grab their portfolios, check their tracking sheet for the periodic table, and sort themselves out.1 There are a couple of options at each table along with green, yellow, and red cups to let me know who needs attention. I spend about two minutes at each table to clear up any confusion or problem and spend the rest of the period skittering around the class like a crab. Good times.
This is certainly possible without topic scales. But self-evaluation and self-tracking makes this so much easier.
1: I still have to send three or four kids per class to different spots because they want to sit with their friends instead of work on their weaknesses. I would blame it on being 8th graders, but really I would have done that from K to college. In fact, I still do that at every PD session we have in my district.