Tags, interaction, and learning

In Holland's model, tags direct the attention of agents toward certain features while disregarding others, thus facilitating selective interaction. In effect, tags identify and categorize phenomena, thus setting the boundaries of aggregates, or groups. Practically, that means that students recognize salient features of other students, thus forming groups that last the semester. Those features tend to be ethnicity, language, and gender. Tags are also values. When students work in groups, some value consensus models of interaction while others prefer more aggressive competition models. These values lead students to continue working with those of the same values and avoiding those of different values. With some groups, age tags operate. With the Chinese students I've had in my classes, the eldest one seemed to be a spokesperson for the rest, regardless of gender. Because tags regulate the formation of groups and networks, having an awareness of the mechanism of tagging can provide a new stance from which to see bottlenecks and lever points of classroom interaction and learning.

So, what/where are the bottlenecks and lever points of classroom interaction and learning?