There's a risk in taking note of some of the terms useful in thinking and talking about relationships and systems theory.  Teachers may be tempted to build assignments around them rather than allowing students to gradually become familiar with them through use and context.        Including a representative list of such terms, however, may serve as  a reminder of how much various fields of study and school subjects have in common when the focus is on big, important ideas rather than on specific facts. adaptation boundary cause/effect change chaos communication complexity component/element critical mass cumulative causation cycle duration interaction dynamic equilibrium feedback frequency function inertia lag model morphogenesis multiple causation organization pattern process rate rhythm stability/instability stasis static structure subsystem system tipping point trend variable